Chapter 18 Endocrine Glands Part 1 Flashcards
what two glands integrate 2 body controlling systems and which systems
hypothalamus and pituitary gland
nervous and endocrine
what regulates pituitary gland secretion in response to other hormones, sensory info, emotions
hypothalamus
where is the hypothalamus located
base of brain witch direct connection to pituitary via infundibulum
hypothalamus regulates anterior pituitary via what
blood vessels, where 2 capillary networks are connected by portal veins
the hypothalamus regulates posterior pituiatary via what
neural pathway through infundibulum
the tract in the posterior pituitary arises from what
neurons in paraventricular and suporaoptic nuclei of hypothalamus
nerves or clusters of brain cells
nuclei
what sits in sella turcica of sphenoid bone
pituitary gland
the pituitary gland have arterial blood supply via what
hypophyseal branches of internal carotid arteries
where do the veins in the pituitary gland drain into
dural sinuses
what is an adenohypophysis
anterior pituitary
Glandular epithelium develops as outpocket of roof of oral cavity (Rathke pouch / Pituitary diverticulum), Connection to oral cavity severed. ONLY vascular connection to Hypothalamus via Hypophyseal Portal Veins.
anterior pituitary
anterior pituitary portal system
capillary bed to veins to 2nd capillary bed
what is the role of the pituitary gland
releasing and inhibiting hormones in ventral hypothalamus to anterior pituitary quickly
what borders post pituitary and has no function in adult, in fetus it produces MSH, role in lower vertebrates
pars intermedia
Neurohypophysis with Infundibulum; Part of the Brain
posterior pituitary
what is the posterior pituitary composed of
neural tissue pituicytes and nerve fibers
what does neural tissue do
regulate release of hormones
what is continous with hypothalamus
PP
embryologic development=
outgrowth of the brain, infundibulum enlarges to form the posterior pituitary
what does the PP release
neurohormones and neuropeptides
the pituitary gland stores hormones but not a
endocrine gland
what does the hypothalamic-hypophyseal tract do
carry hormones to pituitary
what do hypothalamic neurons synthesize
oxytocin and adh
what controls secretion of posterior pituitary hormones
nerve stimulation in hypothalamus
AP’s conducted by Axons of Hypothalamic Neurons through Hypothalamic-Hypophyseal Tract to
posterior pituitary
what is transported down the Axons of Hypothalamic-Hypophyseal Tract to Posterior Pituitary
oxytocin and ADH
where are oxytocin and ADH stored
in axon terminals in PP
Hypothalamic Neurons fire & AP’s arrive at Axon terminals ->
oxytocin and ADH release into blood
once oxytocin and ADH are in the blood what happens
travel through it and bind to receptors on target cells to influence tissue activity
there are releasing and inhibiting hormones in anterior or posterior pituitary
anterior
releasing hormones=
stimulate anterior pituitary hormone secretion
inhibiting hormones=
inhibit anterior pituitary hormone secretion
hypothalamic neurons synthesize what in anterior pituitary
synthesize releasing or inhibiting hormones
neuron stimulation in hypothalamus controls secretion of releasing or inhibiting hormones into
primary capillary plexus of hypothalamus
hypothalamic hormones travel through the
portal veins to anterior pituitary
anterior pituitary secretes hormones into
secondary capillary plexus (in response to releasing hormones)
if it is inhibiting hormones it causes
prevention of hormone secretion
after it goes to capillary plexus
it travels via bloodstream and bind to receptors on target cells and influence tissue activity
what does growth hormone releasing hormone do
increase GH level
what does growth hormone inhibiting hormone do
inhibit GH and TSH secretion
what does thyrotrophin releasing hormone do
increase tsh level
what does corticotropin releasing hormone do
increase acth level
what does gonadotropic releasing hormone do
increase fsh and lh levels
what does prolactin inhibiting hormone do
inhibits prl secretion
what is nervous tissue only
posterior pituitary
antidiuretic hormone is also called
vasopressin
vasopressin causes increase of what with signficiant secretion
BP
what is ADH role
maintains water balance, causes water resorption and prevents urine formation
what does ADH act on
kidney tubules
ADH is triggered by
pain
low bp
nicotine
morphine
barbituates
what is adh made by
neuron cell bodies in SO nuclei of hypothalamus, stores in post pit.
inference of adh:
surgical removal of post. pit. which results in hormone shortage
rate of secretion is dependent on response to changes in what?
blood osmolality and blood volume
what detects changes in blood osmolality
osmoreceptors
what detect changes in bp
baroreceptors
if osmolality increases and bp decreases what happens to ADH secretion
ADH secreting neurons increase APs
osmotic concentration = number of solute in 1 kg of water x number of particles into which solute dissociates- directly proportionate to concentration of solutes
osmolality
APs go to the post. pit. causing ADH to be released into the blood and causes what to increase
kidney tubules increase water resoprtion
kidney tubules increase water resoprtion which results in
reduced urine amount, increases urine osmalality and decreased loss of blood volume
adh secretion is inhibited by
xs water, diurectics, alcohol
what is from an ADH deficiency, extreme thirst and frequent urination with high urinary output
diabetes insipidus
what causes diabetes insipidus
pit tumor
head trauma = damage to hypothalamus or post pit
if the patient with diabetes insipidus has the capacity to drink enough water to prevent dehydration then will they be ok
yes
what causes a patient to have a life threatening cause of diabetes insipidius
the patient is compromised and unconscious or in a come
what is SIADH
syndrome of inappropriate ADH secretion
what is SIADH due to
neurosurgery
cancer
certain meds
general anesthesia
symptoms of SIADH
brain edema-> fluid retention, headache, disoriented, weight gain, blood dilution
how do you treat SIADH
fluid restriction
follow Na level
slowly correct level or central pontine myelinolysis
what is made by neuron cell bodies in PV nuclei of hypothalamus and stored in post pit
oxytocin
pos feedback for oxytocin
stimulates uterine contraction in childbirth
breastfeeding
used to stop postpartum bleeding
what is a love hormone
oxytocin
what stimulate other glands (endocrine to endocrine), regulate secretory action; basophil cells
tropic hormones
what does thyroid stimulating hormones do
increase TH levels
help with normal development
maintain metabolism
what does adrenocorticotropic hormones do
stimulates adrenal cortex to increase glucocorticoid hormone secretion
when do levels of ACTH peak
in the AM
what trippers ACTH
fever
hypoglycemia
stress
what is a precursor for ACTH
proopiomelanocortin
how many molecules in proopiomelanocortin cleaved into
four
what does follicle stimulating hormone in females do
follicle maturation
estrogen secretion in ovary
what does FSH in males do
produce sperm in testes
what does LH do in females
ovulation and progesterone secretion
what does LH do in males
produce testosterone in interstitial cells stimulates gonads
