Exam II material Flashcards
The endocrine system provides ______ of many tissues
Broadcast regulation
The specificity of the endocrine system is due to:
Receptors
Compared to the nervous system, the responses of the endocrine system are:
Slower but longer lasting
Where does the endocrine system release hormones into?
The blood
List the three functions of hormones:
- Maintenance of Homeostasis
- Growth & Differentiation
- Reproduction
Endocrine organs can be divided into what two categories:
- Major endocrine glands
- Organs containing endocrine cells
Primary function is to make a hormone & release it when the stimuli for release are present:
Major endocrine gland
Organs that happen to have endocrine cells within them, allowing them to release a hormone although their primary function is NOT endocrine regulation:
Organs containing endocrine cells
List the specialized endocrine glands (Major endocrine glands)
- Parathyroid gland
- Thyroid gland
- Pituitary gland
- Adrenal gland
- Pineal gland
List some organs that contain endocrine cells, but their primary function is NOT endocrine regulation:
- Hypothalamus
- Skin
- Adipose tissue
- Thymus
- Heart
- Liver
- Stomach
- Pancreas
- Small intestine
- Kidneys
- Gonads
A hormone that causes secretion of a hormone by an endocrine gland
Tropic hormone
How do we classify hormones?
Based on their strucutre
What are the three classifications of hormones?
- Proteins & polypeptides
- Steroids
- Tyrosine derivatives
Describe the time period in which protein/polypeptide hormones are made and released:
Made in advance & stored in vesicles until signaled for release
Protein/polypeptide hormones are synthesized first as:
Preprohormones
The preprohormone will be converted into a:
Prohormone
In protein/polypeptide hormones, what is packed into vesicles in the endocrine cell prior to secretion?
Prohormone
After the prohormone is cleaved, it is now:
Active hormone
The pneumonic for protein/polypeptide hormones:
Protein/Polypeptide = Pre & Pro hormone (all begin with Ps)
In addition to the active hormone, what is released when the prohormone is cleaved?
Inactive fragments
What is the first thing to be cleaved from preproinsulin?
Signal peptide
After the signal peptide is cleaved from preproinsulin what occurs?
Protein folding
Following cleavage of the signal peptide from preproinsulin & protein folding, what results:
Proinsulin
Proinsulin is stored in:
Vesicles
Upon receiving a signal for release into the bloodstream, what is cleaved from proinsulin to convert it to active insulin?
C-peptide
Along with insulin release into the bloodstream, what is also released?
C-peptide
If you wanted to measure someones baseline endogenous production & release of insulin you could measure the:
C-peptide levels in the bloodstream
Protein & polypeptide hormones are often made as an:
Inactive precursor
The inactive precursor of protein & polypeptide hormones:
Preprohormone
What does the signal peptide in insulin serve as?
A marker that tells the cell that insulin needs to undergo exocytosis
Where are the receptors located for protein/polypeptide hormones?
In the plasma membrane
Describe the time period in which steroid hormones are made & released:
Made & released on demand
Where are the receptors located for steroid hormones?
Located inside the cell
Why are steroid hormone receptors located inside the cell?
Because steroid hormones can cross the plasma membrane & bind to internal receptors on target cells
Hormones from the hypothalamus, anterior pituitary, posterior pituitary & pancreas:
Protein/polypeptide
Hormones from the adrenal cortex, ovaries & testes:
Steroid hormones
Steroid hormones are synthesized from:
(derivatives of)
Cholesterol
What are two hormones that are derived from cholesterol that are STRUCTURALLY very similar?
Aldosterone & Cortisol
DHEA, Androstenedione, Testosterone & Estradiol are all steroid hormones involved in:
Reproduction
What determines what steroid hormone will be produced from the precursor cholesterol?
The complement of enzymes present
Describe the time period present in which amine hormones are made & released:
Made early and stored until secreted
Amine hormones are derived from:
Amino acid Tyrosine
Thyroid hormone, Epinephrine & Norepinephrine are all:
Amine hormones
Epinephrine & Norepinephrine are both:
Adrenal medullary neurohormones
Thyroid hormones bind to the protein:
Thyroglobulin
Epinephrine & Norepinephrine are stored in vesicles & released via:
Exocytosis
Structurally what is the difference between T3 & T4:
The number of iodide atoms attached
What is the precursor to Epinephrine & Norepinephrine?
Dopine
Hormones released into circulation can either circulate ____ or ________
Freely or with binding proteins
The majority of ____, ____ & ____ hormones circulate in their free form:
Amines, Peptide/Protein hormone
What is the exception to most amines circulating in their free form & why?
Thyroid hormone
Its double ring structure makes it soluble enough to where it needs help getting through the plasma
Describe the solubility of amines and peptide/proteins hormones:
Water soluble
_____ & ____ hormones circulate bound to specific transport proteins
Steroid & Thyroid
Some binding proteins are specific for a given hormone, but some plasma proteins such as ___ & ____ can bind to many hormones
Globulin & Albumin
Prevalent protein in the plasma that functions as transportation for a lot of different things such as lipid soluble hormones & fatty acids
Albumin
Most binding proteins are synthesized in the:
Liver
Patients with a compromised/dysfunctional liver may show signs of:
Endocrine deficiencies
Why might a patient with a compromised liver show endocrine deficiencies?
Because most binding proteins are synthesized in the liver & if you can’t make your binding proteins you can’t get enough hormone into the blood
It is always the ______ version of the hormone that binds to receptors & affects the target cell:
Free version (binding protein stays in blood vessel)
The constitutive level of plasma hormones
Basal level
The stimulated level of plasma hormones
Peak levels
The variable pattern of hormone release (peaks & troughs) is determined by the interaction & integration of multiple control mechanisms which include: (4)
Hormonal
Neural
Nutritional
Environmental
When a hormone is constantly secreted in small amounts at a time:
Tonic release
Hormone fluctuations that happen dependent on the time of day
Circadian rhythm
Give an example of a hormone that follows circadian rhythm release:
Cortisol
When does cortisol levels spike?
In the early morning hours
What can work in addition to circadian rhythm release to regulate the release of hormones:
Stimuli
Growth hormone is released during sleep making it following a circadian rhythm release pattern but also displays:
Pulsatile secretion
Secreted in pulses (secretes, stops, secretes, stops)
Pulsatile secretion
The location of the hormone receptor depends on the ______ properties of the hormone
Chemical
The chemical properties of the hormone that determine the location of the hormone receptor can be:
Lipophobic & Liphophillic
Ligand/Receptor binding demonstrates:
- Specificity
- Affinity
- Saturation
Which classes of hormones bind to plasma membrane receptors?
Polypeptide/Protein hormones
Amine hormones*
What amine hormone does not bind to plasma membrane receptors? (except to the rule)
Thyroid hormone
Which class of hormones binds to nuclear receptors?
Steroid hormones + thyroid hormone
Which amine hormones bind to plasma membrane receptors?
Epinephrine & Norepinpehrine
What type of receptors would the following hormones bind to & why?
- Glucagon
- Angiotensin
- GnRH
- SS
- GHRH
- FSH
- LH
- TSH
- ACTH
Plasma membrane receptors- they are peptide/protein hormones
In general many of the receptors that proteins/peptide hormones & amine hormone bind to in the plasma membrane are:
G-protein coupled receptors (GPCRs)
Involved in turning on or off a protein that is already in the cell:
Plasma membrane receptors
What class of hormone receptors are involved in causing a change in gene expression to get a biological response?
Nuclear receptors
Class of hormone receptors involved in making new proteins:
Nuclear receptors
Thyroid hormone & steroid hormones bind to receptors located in:
Either the cytoplasm or the nucleus
Once the steroid hormone or thyroid hormone binds to the receptor located in the nucleus or cytoplasm what occurs next?
Transformation of receptor to expose DNA-binding domain
Following binding of the steroid hormone or thyroid hormone to the receptor & transformation of the receptor to expose the DNA-binding domain what next occurs?
Binding to enhancer-like element in DNA
Examples of plasma membrane hormone receptors:
- GPCR
- Tyrosin kinase
Why do plasma membrane hormone receptor numbers vary greatly in different target tissues:
Provides a way to achieve specific tissues activation
What are two examples of plasma membrane hormone receptors that are more distributed:
- Thyroid hormone receptors
- Insulin receptors
Why are thyroid hormone receptors & insulin receptors more sidled distributed?
Because their actions are something that most cells participate in
How do IGF-1 & Insulin work?
By activating a tyrosine kinase receptor
If it is plasma membrane receptor generally it will activate or inhibit _____ to ______
An existing protein to yield a faster response
Where are nuclear hormone receptors located?
Cytoplasm or nucleus
Nuclear hormone receptors typically leads to:
Formation of new proteins
Nuclear hormone receptors all act to:
Increase or decrease gene expression
In a nuclear hormone receptor, the hormone receptor complex binds to a ______ in the _____ region of the gene which leads to either the activation or repression of ______
Hormone responsive element
Promotor region
Gene transcription
Because nuclear hormone receptors binding a hormone leads to the formation of a new protein, describe the timeline involved:
It takes a little bit longer to get the response & the response will last a bit longer
Hormones that bind to nuclear receptors (thyroid hormone & steroid hormones) undergo _____ to get through the plasma membrane
SImple diffusion
The body often releases multiple hormones:
At the same time
What are the effects of combined hormone actions: (4)
- Antagonism
- Additive
- Synergistic
- Permissiveness
When two hormones change one variable in opposite directions:
Antagonsim
When the response of hormone is equal to the two portions that each hormone provide (2+3=5)
Additive
When the combined hormone response is greater than the individual responses of each hormone added together (2+3=10)
Synergistic
The presence of one hormone is necessary for another hormone’s maximum affect:
Permissiveness
Determine which hormone interaction is being described in the following situation:
Parathyroid increases plasma calcium levels; Calcitonin decreases plasma calcium levels:
Antagonism
Determine which hormone interaction is being described in the following situation:
Glucagon, cortisol & epinephrin all increase blood glucose more than the sum of their individual effects:
Synergism
Determine which hormone interaction is being described in the following situation:
Thyroid hormone causes expression of B adrenergic receptors in bronchiolar smooth muscle:
Permissive
What determines whether the negative feedback will be short loop or long loop?
The location of the hormone that acts as negative feedback in the system
When the last hormone in the pathway inhibits the system upstream
Long loop negative feedback
When an intermediate hormone in the pathway inhibits the system upstream
Short loop negative feedback
Feedback where the hormonal product or an intermediate hormone enhances the hormone secretion:
Positive feedback
Causes an endocrine gland to secrete a hormone
Tropic hormone
Stabilizes the system & prevents over-secretion:
Negative feedback
Hormones that have other endocrine glands as there targets:
Tropic hormones
A tropic hormone from the hypothalamus that acts on the anterior pituitary to release TSH
Thyroid releasing hormone (TRH)
Thyroid releasing hormone (TRH) comes from:
The hypothalamus
TRH acts on the:
Anterior pituitary
TSH (Thyroid stimulating hormone) is released from:
The anterior pituitary
TSH is released from the anterior pituitary & acts on:
The thyroid gland
In the regulation of thyroid hormone, a stimulus causes the hypothalamus to secrete ____ which acts on the ______
TRH
Anterior pituitary
In the regulation of thyroid hormone, _____ cells in the anterior pituitary release _____
Thyrotropic cells
Thyroid stimulating hormone
In the regulation of thyroid hormone, TSH stimulates _____ cells of the thyroid gland to release _____
Follicular cells
Thyroid hormone (TH)
Thyroid hormone produces effects in the body that include:
- Increase in metabolic activity
- Increase in body temperature
In the regulation of thyroid hormone, thyroid hormone stimulates target cells to increase ____ activities resulting in an increase in basal body temperature
Metabolic activities
In the regulation of thyroid hormone, increased body temperature is detected by the hypothalamus & the secretion of _____ by the hypothalamus is ____
TRH
Inhibited
In the regulation of thyroid hormone, thyroid hormone also blocks TRH receptors on thyroid cells inhibiting synthesis & release of ____. Both effects indirectly dampen _____ production in the thyroid
TSH
TH
Thyroid hormone working to negatively feedback is an example of:
Long loop negative feedback
If hormone levels are NOT kept in balance via negative feedback mechanisms what occurs?
Endocrine disorders/Pathologies
Enlargement of the thyroid due to increased or decreased thyroid hormone levels:
Thyroid goiter
Disease characterized by increased cortisol levels:
Cushings disease
Abnormality in the last endocrine organ secreting the hormone leading to either hypo- or hyper-secretion:
Primary endocrine disorder
List the causes of primary hyposecretion:
- Partial destruction of the gland
- Dietary deficiency
- Enzyme deficiency required for hormone synthesis
List the causes of primary hypersecretion:
- Endocrine gland tumor
Abnormality in tropic hormone leading to either hypo- or hyper-secretion:
Secondary endocrine disorder
List the causes of secondary hyposecretion:
A lack of sufficient tropic hormone
List the causes of secondary hypersecretion:
A tumor (either in an endocrine gland that secretes tropic hormones or in a non-endocrine tissues that secretes hormones)
When you see an endocrine hormone disturbance as a result of cancer:
Paraneoplastic endocrine syndrome
When you think of primary endocrine dysfunction you should think:
LAST gland in pathway
Type of diagnostic endocrine function test in which you give something to make hormone levels go up to see if hormone levels actually go up:
Type of diagnostic endocrine function test in which you give something to inhibit the hormone levels in question & look to see if that actual works:
Stimulation test
Suppression test
Suppression test would be used to detect what type of endocrine dysfunction:
Hyperfunction
List the types of diagnostic test used to examine endocrine function (7):
- Plasma hormone levels
- Autoantibodies
- Urine hormone/hormone metabolite levels
- Stimulation tests by administration of tropic or stimulating hormone
- Suppression tests when hyperfunction of endocrine organ is suspected
- Measurement of hormone receptor presence , number & affinity
- Imaging
Stimulation tests work by administering a ____ hormone:
tropic or stimulating
An example of measuring hormone receptor presence as an endocrine diagnostic function test:
Estrogen receptors in breast tumors
What autoantibodies might be tested when doing diagnostic tests of endocrine function:
- Hashiomoto thyroiditis
- Type I DM
- Graves disease
- Addison disease
- Autoimmune hypoparathyroidism
Glucagon, Angiotensin, Gonadotropin releasing hormone (GnRH), Somatostatin (SS), Growth hormone releasing hormone (GHRH), Follicle stimulating hormone (FSH), Lutenizing hormone (LH), Thyroid stimulating hormone (TSH), Adrenocorticotropin hormone (ACTH)
Are all ____ hormones
When are they made?
Polypeptide/protein hormones
Made in advance & stored until use
Epinephrine & norepinephrine are ____ hormones
When are they made?
Amine hormones
Made in advance and then stored
Thyroid hormone (TH) is a ____ hormone
When is it made?
Exception: amine hormone
Made in advance and then stored but does bind to nuclear receptors
Aldosterone, Cortisol, Estradiol, testosterone, also mineralocorticoids, glucocorticoids, and androgens are all _____ hormones
When are they made?
Steroid hormones
Made on demand
List things that stimulate growth hormone (GH) release:
GHRH
Dopamine
Catecholamines (in times of stress & exercise)
Excitatory amino acids
Thyroid hormone
Fasting (Hypoglycemia)
List things that inhibits growth hormone (GH) release:
Somatostatin (SS)
IGF-1 (because of negative feedback)
Glucose (at high levels- hyperglycemia)
Free fatty acids
GHRH, Dopamine, Catecholamines, excitatory amino acids and thyroid hormone would cause ______ of growth hormone release
Stimulation
Portion of the pituitary that is truly filled with endocrine cells- a true endocrine gland:
Adenohypophysis
Adenohypophysis is referring to what portion of the pituitary gland:
Anterior pituitary
Portion of the pituitary that contains axon terminals of hypothalamic neurons:
Neurohypophysis
Neurohypophysis is referring to what portion of the pituitary gland:
Posterior pituitary
The pituitary gland is locked in the ______ ventral to the ______
Sella turcica
Diaphragma sella
List the hormones secreted by the anterior pituitary: (6)
- FSH
- LH
- Adrenocorticotropin
- Thyroid-stimulating hormone
- Prolactin
- Growth hormone
List the hormones secreted by the posterior pituitary: (2)
- ADH/Vasopressin
- Oxytocin
The pituitary gland secretes _____ hormones
Peptide hormones
What are the most prevalent cells in the anterior pituitary & what do they secrete?
Somatotrophs
Growth hormone
What percentage of cells in the anterior pituitary do somatotrophs comprise?
30-40%
What is the second most prevalent type of cell in the anterior pituitary & what do they secrete?
Corticotrophs
ACTH
What percentage of cells in the anterior pituitary do corticotrophs comprise?
20%
Aside from corticotrophs & somatotrophs, what types of cells makeup the anterior pituitary & what do they secrete?
Thyrotrophs - TSH
Gonadotrophs- LH & FSH
Mammaotrophs- Prolactin
Adenomas involving somatotropin cells can cause _____ if occurring in children before the closing of long bones (epiphyseal plates) or _____ in adults with musculoskeletal, neurologic, and other medical consequences
Gigantism
Acromegaly
Benign tumor of epithelial cells that makes hormones:
Adenoma
Endocrine cells are derived from:
Epithelial cells
If a benign tumor is involved in somatotropic cells this would cause over secretion of:
Growth hormone
Majority of cells in the anterior pituitary are devoted to making _____ & _____
GH & ACTH
Neurons in the hypothalamus synthesize & secrete ______ hormones that control endocrine cells in the ______
Hypothalamic releasing/inhibiting hormones
Anterior pituitary
The hypothalamic hormones are released into the ______ in the ______ (in the hypothalamus)
Primary capillary plexus
Median eminence
Responsible for carrying the hypothalamic hormones to the sinuses of the anterior pituitary gland:
Hypothalamic-hypophyseal portal blood vessels
Hypothalamic-hypophyseal portal blood vessels carry the hypothalamic hormones to the ______ of the anterior pituitary gland
Sinuses
Regulation of anterior pituitary secretion
- ______ releases hormones that enter into the blood
- Hormones travel through the ________
- Hormones will continue down through the capillary bed to the ______ wire they can leave the blood & regulate activity of the endocrine cells
- Hypothalamus
- primary capillary plexus
- Sinus
Two capillary beds in series
Portal system
The hypothalamic-hypophyseal portal vessel is comprised of:
Primary capillary plexus + sinus
The hypothalamic hypophyseal portal allows for:
Communication from the hypothalamus to the anterior pituitary
Where do releasing hormones come from?
Hypothalamus
Where do stimulating hormones cone from?
Anterior pituitary
The hypothalamic regulatory hormones bind to_____ in the various endocrine cells of the anterior pituitary
G-proteins coupled receptors
Following the binding of the hypothalamic hormones to the G-protein coupled receptors in the anterior pituitary, what is responsible for stimulating or inhibiting anterior pituitary hormone secretion?
Second messengers (cAMP via Adenylate cyclase, IPs & DAG via Phospholipase C)
Growth hormone inhibiting hormone (GHIH) =
Somatostatin
Prolactin inhibiting hormone (PIH) =
Dopamine
Growth hormone is secreted by somatotrophs in the anterior pituitary. The releasing hormone (secreted by hypothalamus) would be _____ (gas) while the inhibiting hormone would be ______ (breaks)
GHRH
GHIH
GH, a peptide hormone acts _____ on target tissues and as a ______ to the liver
Directly
Tropic hormone
GH, a peptide hormone acts directly on target tissues ad as a tropic hormone to the _____ which releases _____
Liver
IGF1
In what situation might growth hormone significantly increase and quickly?
Prolonged starvation/fasting
Growth hormone acts tropically on the liver to activate _____ a cell signaling pathway that causes the release of _____
JAKSTAT
IGF1
A cell signaling pathway in the liver activated by GH that responds by release of IGF1
JAKSTAT
What are some target tissues of growth hormone? (6)
- Liver
- Chondrocytes
- Muscle cells
- Adipose cells
- Anterior pituitary (short loop negative feedback)
- Hypothalamus (long loop negative feedback)
If GH acts on chondrocytes what results?
- increased amino acid uptake
- Increased protein synthesis
GH acting on chondrocytes to increase amino acid uptake as well as protein synthesis is ultimately necessary for:
Linear growth
In addition to growth hormone acting on chrondocytes being necessary for linear growth what is also necessary for linear growth:
IGF1
GH can act on muscles to:
Increase protein synthesis
In addition to growth hormone acting on muscle to increase protein synthesis what is also necessary for protein synthesis:
IGF1
In excess how does growth hormone affect adipose tissue?
Anti-insulin action
What are two locations of negative feedback of growth hormone:
- Directly feeding back to anterior pituitary (short loop)
- Feeding back to hypothalamus (long loop)
If negative feedback via growth hormone occurs on the hypothalamus what hormone may be released:
Somatostatin
Describe the secretion of growth hormone:
Pulsatile secretion; lower concentration during day with highest levels a few hours after sleep
When is growth hormone secreted at the highest levels:
A few hours following sleep
GH secretion can be stimulated by: (5)
- Starvation (protein deficiency)
- Fasting (hypoglycemia)
- Acute stress
- Exercise
- Excitement
The secretion of GH during the neonatal period can be described as:
The secretion of GH during childhood can be described as:
The secretion of GH during puberty can be described as:
The secretion of GH during adulthood can be described as:
- High secretion
- Decreased secretion
- Peak levels of secretion
- Decreased secretion with age
Stimulation of GH release: (5)
- GHRH
- Dopamine
- Catecholamines
- Excitatory amino acids
- Thyroid hormone
Inhibition of GH release: (4)
- Somatostatin
- IGF1 (due to negative feedback)
- High levels of glucose
- High levels of free fatty acids
Many of the growth & metabolic effects of GH are mainly produced by:
IGFs
IGFs may also be called:
Somatomedins
IGF1 is produced in most tissues and acts on neighboring cells in a ____ manner
Paracrine
The major site of IGF1 synthesis:
The liver
How many IGF binding proteins are there?
6
_____ in adults is one of the main growth promoting insulin-like growth factors:
IGF1
Osteocytes responding to mechanical sensors can release:
IGF1
Osteocytes responding to _____ can release IGF1:
Mechanical sensors
After osteocytes release IGF1 what happens?
IGF1 binds to receptors on osteoblasts to enhance bone formation
Mechanisms of actions of GH & IGF1:
Growth in nearly all tissues of the body, mainly IGF1 occurs through what mechanisms:
- increased cell size
- mitosis
- Differentiation of bone & muscle cells
Mechanisms of actions of GH & IGF1:
What are the overall outcomes of the affects of GH & IGF1 causing growth in nearly all tissues in the body:
- increased organ size
- increased organ function
- increased linear growth
- increased lean body mass
Mechanisms of actions of GH & IGF1:
Effect of increased amino acid uptake and protein synthesis result in:
Increased lean body mass
Mechanisms of actions of GH & IGF1:
How does this effect glucose?
Reduced glucose utilization
Mechanisms of actions of GH & IGF1:
Reduced glucose utilization is due to:
- decreased cellular uptake
- increased hepatic glucose production
- increased insulin secretion
Mechanisms of actions of GH & IGF1:
The reduced glucose utilization can lead to:
Insulin resistance; diabetogenic
Mechanisms of actions of GH & IGF1:
Describe the effects on fatty acids:
Mobilization of fatty acids from adipose tissue (lipolysis)
The mobilization of fatty acids from adipose tissue:
lipolysis
Mechanisms of actions of GH & IGF1:
Lipolysis results in:
Increased FFA in blood and use of FFA for energy
Before fusion of the epiphyseal plates, GH & IGF1 stimulate:
- Chondrogenesis
- Widening of the epiphyseal plates
Following GH and IGF1 stimulating chondrogenesis & widening of the epiphyseal plates, what occurs:
Bone matrix deposition stimulating linear growth
In adults, GH and IGF1 play a role in regulating the normal physiology of:
Bone formation
In adults, how do GH & IGF1 play a role in regulating normal physiology of bone formation?
By increasing bone turnover
How do GH and IGF1 stimulate the increase in bone turnover (thereby regulating bone formation):
- activation of osteoblasts (mainly)
- Increase bone resorption via osteoclasts (lesser extent)
Kids: GH & IGF1 =
Adults: GH & IGF1 =
Chondrogenesis
Increased bone turnover
Osteoblast are of what origin?
Mesenchymal precursor cells
What is responsible for the formation of active osteoblasts from the osteoblasts precursors?
IGF1
Gigantism occurs in ____
Acromegaly occurs in _____
Children
Adults
Excess growth hormone in children leading to gigantism is typically caused by:
Pituitary tumor (90%)
What areas are commonly involved in pituitary tumors that give rise to gigantism?
Sella & cavernous sinus
Tumor causing excessive growth hormone release:
Somatotropin adenoma of pituitary
Describe the facial features that may be associated with gigantism/acromegaly: (4)
Coarse facial features
Large fleshy nose
Frontal bossing
Jaw malocclusion
Coarse facial features including a large fleshy nose, frontal bossing & jaw malocclusion are collectively reffered to as:
Acromegalic facies
What issue with the thyroid may occur with gigantism/acromegaly?
Goiter
Describe the potential effects on the heart & what conditions may result due to gigantism/acromegaly
Cardiomegaly
Hypertension
Coronary heart disease
Describe the chest & spine in individuals effected by acromegaly/gigantistm:
Barrel chest
Kyphosis & hyperostosis
The abnormal glucose tolerance & secondary insulin resistance in an acromegaly/gigantism effected individual may result in:
Diabetes Mellitus
Growth hormone shifts the body from using ___ to ____ for metabolism
Carbs to fats
Describe the reproductive consequences on individuals with acromegaly/gigantism:
Male sexual dysfunction & menstrual disorders
Describe what can occur due to the thicken skin & hypertrophy of sebaceous & sweat glands in gigantism/acromegaly:
Hyperhidrosis & oily skin
Hyperhidrosis & oily skin in acromegaly/gigantism can occur due to:
Thickened skin (hypertrophy of sebaceous & sweat glands)
What can occur in the joints of individuals with gigantism/acromegaly:
Degenerative arthritis
Describe the neuronal effects caused by gigantism/acromegaly:
Parathesias due to peripheral neuropathy
What is a potential treatment for pituitary micro adenoma:
Adenectomy via transphenoidal approach followed by medication
Oral manifestations of GH excess: (7)
- Thick rubbery skin, enlarged nose, thick lips
- Macrocephaly
- Macrognathia
- Disproportionate mandibular growth
- Anterior bite & malocclusion
- Macroglossia, Dyspnea, Dysphagia, Dysphonia, Sialorrhea
- Hypertrophy of pharyngeal & laryngeal tissues
Enlarged head=
Enlarged jaw=
Macrocephaly
Macrognathia
The disproportionate mandibular growth cause by excess GH includes:
Mandibular prognathism- jaw gets forward
Generalized diastemata- teeth separation
The anterior open bites & malocclusion caused by excess GH is due to:
Combination of macrognathia & tooth migration
Define each:
Macroglossia
Dyspnea
Dysphagia
Dysphonia
Sialorrhea
Enlarged tongue
Difficulty breathing
Difficulty swallowing
Difficulty speaking
Slobbering/droolinh
The hypertrophy of the pharyngeal & laryngeal tissues due to excess GH can lead to ________ & how?
Sleep apnea due to the increased growth of pharyngeal & laryngeal tissues obstructing the airway
What are the causes of growth hormone deficiency: (5)
- Hypothalamic disorders
- Mutations
- Combined pituitary deficiencies
- Radiation
- Psychosocial deprivation
Combined pituitary hormone deficiencies:
Panhypopituitarism
What type of mutations may lead to GH deficiency:
GHRH receptor
GH gene
GH receptor
IGF1 receptor
A decrease in GHRH or an increased in GHIH can lead to
Growth hormone deficiency
What depends on the time of onset & severity of hormone deficiency:
(talking about growth hormone)
Clinical manifestations
The clinical manifestations caused by complete growth deficiency include: (4)
- Slow linear growth rates (shorter stature)
- Normal skeletal proportions
- Pudgy, youthful appearance (decreased lipolysis)
- In the setting of cortisol deficiency hypoglycemia
The most common form of dwarfism that is caused by an autosomal dominant conditions that results from a mutation in the FGF-3 receptor in cartilage & brain:
Achondroplasia
Mutation in the FGF-3 receptor in the cartilage & brain makes the receptor overly active and it inhibits cartilage growth at growth plates so:
Limb growth is reduced (growth of trunk is not impacted)
Mutated receptor involved in achondroplasia:
FGF-3
Oral manifestations of GH deficiency include:
- Disproportionate delayed growth of the _____ & ____ = ____ facial appearance
- _____ & ____ of the ___ regions of the jaws are abnormal & may be disproportionately smaller than adjacent structures
- Solitary _____
- Eruption of primary & secondary dentition & shedding of deciduous teeth are ______
- Skull & facial skeleton; small
- Tooth formation & growth; alveolar
- Median maxillary central incisor
- Delayed
How are the oral manifestations of GH deficiency managed:
Correction of dental & skeletal malocclusions
Incisor defects in a child with GH deficiency occurs in both:
Primary & permanent dentition
Oral manifestations of GH deficiency includes tooth formation & growth of alveolar regions of the jaw are abnormal & may be disproportionately smaller than adjacent anatomic structures this can cause:
- Tooth crowding & malocclusion
- Plaque accumulation
- Poor oral hygiene
- Gingivitis & perio disease
The posterior pituitary contains ~100,000 _________ whose cell bodies are in the_______
Unmyelinated axons of neurons
hypothalamus
Areas of concentrated neuronal cell bodies in the hypothalamus that have axons that go through the infundibulum with their synaptic terminals located in the posterior pituitary gland
Paraventricular nucleus & Supraoptic nucleus
The paraventricular nucleus produces ______
Oxytocin
The supraoptic nucleus produces _____
ADH
List all at the names for the abbreviation ADH:
- Antidiuretic hormone
- Arginine Vasopressin (AVP)
Both ADH and Oxytocin are classified as:
Neurohormones
Both ADH and oxytocin are neurohormones made of:
Polypeptides of nine amino acids
While the paraventricular nucleus secretes Oxytocin, and the supraoptic nucleus secretes ADH, they both have the ability to:
Secrete some of the other neurohormone
Describe the similarities between ADH & oxytocin
VERY SIMILAR STRUCTURE & both amine hormones
What are the two primary functions of ADH
- Vasoconstriction (smooth muscle & blood vessels)
- Antidiuretic (holds on to water)
ADH/AVP mechanism of action:
- Contraction of vascular smooth muscle via _____
V1 Receptors
When ADH causes contraction of vascular smooth muscle through V1 receptors what results?
Increases blood pressure
V1 stands for:
Vasopressin-1 receptor
When ADH acts on V1 receptors what occurs?
Contraction of vascular smooth muscle (blood vessels) leading to increase in BP
ADH/AVP mechanism of action:
Functions in the renal renal tubules via:
V2 Receptors
Where are the V2 receptors (for ADH) located?
Late distal tubule & collecting duct
What results when ADH binds to V2 in the last distal tubule & collecting duct?
AQP-2 proteins are inserted into the apical membrane of tubular epithelial cells
Where is aquaporin-2 inserted following ADH binding to V2 receptors?
The apical membrane of tubular epithelial cells
Following ADH binding to V2 receptors in the renal tubules and AQP-2 being inserted into the apical membrane of tubular epithelial cells what results?
This allows for water reabsorption (in accordance with AQP3 & AQP4 on the basolateral membrane
For water reabsorption to occur through AQP2 what also has to be present?
AQP3 & APQ4 on the basolateral membrane
V2 receptors in the late distal tubule and collecting duct are _____ receptors
GPCR
Although water can go through the apical membrane via simple diffusion, the aquaporins allow for:
Water channels so a lot more reabsorption can occur
