PCOL MIDTERM 4 Flashcards
System of ductless glands that secrete hormones
Endocrine system
Hormones are
“messenger molecules”
Endocrine system characterization
- Circulate in the blood
- Act on distant target cells
- Target cells respond to the hormones for which they have receptors
- The effects are dependent on the programmed response of the target cells
Hormones are just
Molecular triggers
2 Types of Endocrine Organs
- Purely Endocrine Organs
- Endocrine Cells in other organs
What Organs are Purely Endocrine
- Pituitary gland
- Pineal gland
- Thyroid gland
- Parathyroid glands
- Adrenal: 2 glands
- Cortex
- Medulla
Endocrine cells in other organs
- Pancreas
- Thymus
- Gonads
- Hypothalamus
The control of metabolism, growth, and reproduction is mediated by a combination of neural and endocrine systems located in the hypothalamus and pituitary gland.
Hypothalamic- pituitary endocrine system
Mechanism of Hormone release
(a) Humoral
(b) Neural
(c) Hormonal
In response to changing levels of ions or nutrients in the blood
Humoral
Stimulation by nerves
Neural
Stimulation received from other hormones
Hormonal
It is the master endocrine organ
Hypothalamus
It is the master endocrine organ
Hypothalamus
It secretes releasing / inhibiting hormones
Hypothalamus
Pituitary gland consist of
- Anterior lobe
- Posterior lobe.
Connected to hypothalamus by a stalk of neurosecretory fibers and blood vessels, including a portal venous system that drains the hypothalamus and perfuses the anterior pituitary.
Pituitary gland
The posterior lobe hormones are synthesized in the _______ and transported via the _______in the stalk of the pituitary to the posterior lobe, from which they are released into the circulation.
(1) Hypothalamus
(2) Neurosecretory fibers
Sits in hypophyseal fossa: depression in sella turcica of sphenoid bone
Pituitary gland
What are the Divisions of Pituitary Gland
- Anterior Pituitary
- Posterior Pituitary
Pituitary secretes, how many hormones?
9
Anterior pituitary aka
Adenohypophysis
Posterior pituitary aka
Neurohypophysis
What are the hormones in Anterior pituitary
- TSH
- ACTH
- FSH
- LH
- GH
- PRL
- MSH
Full name of the ff:
1. TSH
2. ACTH
3. FSH
4. LH
5. GH
6. PRL
7. MSH
- (TSH) Thyroid-Stimulating Hormone or Thyrotropin
- (ACTH) Adrenocorticotropin
- (FSH) Follicle-Stimulating Hormone
- (LH) Luteinizing Hormone
- (GH) Growth hormone
- (PRL) Prolactin or (LTH) Luteotropic hormone
- (MSH) Melanocyte-Stimulating Hormone
What are the hormones in Posterior pituitary
- ADH (antidiuretic hormone), or vasopressin
- Oxytocin
Drugs that mimic or block the effects of hypothalamic and pituitary hormones have pharmacologic applications in three primary areas
Hormonal Agents
Drugs that mimic or block the effects of hypothalamic and pituitary hormones have pharmacologic applications in 3 primary areas:
- As replacement therapy for hormone deficiency states
- As antagonists for diseases caused by excess production of pituitary hormones
- As diagnostic tools for identifying several endocrine abnormalities.
GH Hypothalamic Hormone
Growth hormone-releasing hormone (GHRH) (+) Somatostatin (-)
TSH Hypothalamic Hormone
Thyrotropin releasing hormone (TRH) (+)
GH Target Organs
- Liver
- Bone
- Muscle
- Kidney
GH Primary Target Organ Hormone or Mediator
Insulin-like growth factor - I (IGF-1)
TSH Target Organ
Thyroid
TH Primary Target Organ Hormone or Mediator
- Thyroxine
- Triiodothyronine
ACTH Hypothalamic Hormone
Corticotropin releasing hormone (CRH) (+)
ACTH Target Organ
Adrenal cortex
ACTH Primary Target Organ Hormone or Mediator
Cortisol
FSH and LH Hypothalamic Hormone
Gonadotropin releasing hormone (GnRH) (+)
FSH and LH Target Organ
Gonads
FSH and LH Primary Target Organ Hormone and Mediator
- Estrogen
- Progesterone,
- Testosterone
PRL Hypothalamic Hormone
Dopamine (-)
PRL Target Organ
Breast
PRL Primary Target Organ Hormone and Mediator
None
Required during childhood and adolescence
Growth Hormones
Contaminated prions can cause
Creutzfeldt-Jakob disease