HUBS1403 Lecture Notes - Lecture 21: Adrenocorticotropic Hormone, Lipogenesis, Glycogenesis
8 Jun 2018
School
Department
Course
Professor
Hormone Secretions and Actions 2
Adrenal Glands
• Aka Suprarenal glands
• Located on top of each kidney
• Divided into 2 regions
o Outer cortex
o medial medulla
• Covered by a connective tissue capsule
Cortex is divided into 3 regions
• Zona glomerulosa
o Secretes mineralcorticoids
• Zona fasciculata
o Secretes glucocorticoids
• Zona reticularis
o Secretes (weak) androgens
Secretion
Example
Helps Regulate
Controlled by
Mineralocorticoid
Aldosterone
• Major secretion
from adrenal gland
• Helps regulate Na and K by
homeostasis
• Secretion controlled
by the renin-
angiotensin-
aldosterone (RAA)
pathway
Glucocorticoids
• Cortisol (most
produced)
• Cortisone
• Corticosterone
• Protein breakdown
• Glucose formation
• Lipolysis
• Resistance to stress
• Inflammation
• Immune responses
• Secretion regulated
by negative
feedback
Adrenal Androgens
• Major androgen -
dehydroepiandrostero
ne (DHEA)
Males
• After puberty
testosterone is secreted I
much larger quantities so
DHEA has virtually no
effect
Females
• Adrenal androgens
promote libido and are
converted to estrogens
• After menopause, all
female estrogens come
from adrenal androgens
Adrenal Medulla
• Stimulated by sympathetic preganglionic neurons of the autonomic nervous system (ANS)
• Chromaffin cells secrete epinephrine (adrenaline) and norepinephrine (noradrenaline)
• Part of the stress response
o Increases BP, HR via β1 receptors
o Increases glycogenolysis and glycolysis, dilate bronchi, stimulate lipolysis
Pancreas
Document Summary
Adrenal glands: aka suprarenal glands, divided into 2 regions. Located on top of each kidney: outer cortex, medial medulla, covered by a connective tissue capsule. Aldosterone: helps regulate na and k by, major secretion homeostasis from adrenal gland. Secretion controlled by the renin- angiotensin- aldosterone (raa) pathway. Lipolysis: protein breakdown, glucose formation, resistance to stress. Males dehydroepiandrostero ne (dhea: after puberty testosterone is secreted i much larger quantities so. Females: adrenal androgens promote libido and are converted to estrogens, after menopause, all female estrogens come from adrenal androgens. Stimulated by sympathetic preganglionic neurons of the autonomic nervous system (ans: chromaffin cells secrete epinephrine (adrenaline) and norepinephrine (noradrenaline, part of the stress response. Increases glycogenolysis and glycolysis, dilate bronchi, stimulate lipolysis. Pancreas: both an endocrine and exocrine gland. Pancreatic islets: almost all exocrine cells of the pancreas are arranged in clusters called acini, produce digestive enzymes, delivered to the gastrointestinal tract through ducts.
