Physiology: introduction to endo Flashcards
Does the endocrine system consist of endocrine glands, endocrine tissue, and scattered endocrine cells?
Yes
What are neurohormones?
Hormones released by neurons
What are the 3 main groups of neurohormones?
Catecholamines - made by modified neurons in the adrenal medulla
Hypothalamic neurohormones secreted from the posterior pituitary
Hypothalamic neurohormones that control hormone release from the anterior pituitary
The three classes of hormones:
- Steroid hormones also include mineralocorticoids (aldosterone), glucocorticoids (cortisol),
The three classes of hormones:
Receptors:
- Cell surface receptors are usually activated by hydrophilic/lipophilic molecules, and are faster/slower acting
- Nuclear receptors are usually activated by hydrophilic/lipophilic molecules, and are faster/slower acting
- Cell surface receptors are usually activated by HYDROPHILIC molecules, and are FASTER acting
- Nuclear receptors are usually activated by LIPOPHILIC molecules, and are SLOWER acting
Cell surface receptors
- 2 examples of G protein coupled receptor signalling pathways?
cAMP pathway
DAG/IP3 pathway
Example of tyrosine kinase pathway?
Insulin signalling –> leads to GLUT4 translocation to the surface of skeletal muscle/fat cells –> increased glucose uptake
cAMP signalling pathway
Is it involved in ADH V1 or V2 signalling?
V2 signalling (water reabsorption)
Diacylglycerol/inositol triphosphate pathway
- What hormones is it involved in?
GhRH, GRH
Catecholamines
ADH (V1), oxytocin
The rate of free hormone concentration in the EF (and hence the magnitude/strength of a response to a hormone) depends on what 3 factors?
Patterns of hormone secretion
- What hormone is secreted episodically?
- Constantly?
- In a pulsatile manner?
- Diurnally?
Insulin (in response to increased BGLs)
Thyroxine (needed to constantly maintain physiological functions)
LH
Cortisol, growth hormones
