Chapter 77 Adrenocortical Hormones
Main Points:
I Synthesis and Secretion of Adrenocortical Hormones II Functions of the following hormones
* Glucocorticoids Mineralocorticoids Androgens
Hypothalamus CRH
Negative feedback effect of Cortisol on
Circadian Rhythm of Cortisol SecretionAnterior
CRH & ACTH Secretion
Pituitary
ACTH
Cortisol
Adrenal Cortex
Preventable effects Reduce established Infla.
Arthritis, Rheumatic etc
Circulation system
(Permissive effect)
Nerve system
(Enhance Excitability; Memory)
Many types of stress increase cortisol release
Other Effects
Blood system
(Increase red blood cells; Decrease immunocyte )
Anti-inflammation; Anti-Allergy
Carbohydrate Metabolism
a) Stimulation of Gluconeogenesis b) Decreased Glucose Utilization
Serum Glucose↑
(Adrenal Diabetes --- insensitive to Insulin)
Protein Metabolism
III Regulation of Cortisol Secretion
Anatomy and Histology of Adrenal Gland
Cortex
Hormones Secreted from each layer in Cortex and Medulla of Adrenal
(Mineralocorticoids)
‘Moon’ face
Buffalo-like Torso
Purple Stripe
Resist Stress
Stress induced Rapid mobilization of amino acids and fats for energy and synthesis of other substances.
II Regulation of Cortisol Secretion
ACTH Stimulates Cortisol Secretion CRH Control ACTH Secretion
Stress
Stress increase secretion of CRH and subsequently ACTH
How to terminate Cortisol following chronic exogenous
cortisol supplement???
Respiratory system
(Lung maturation and Surfactant production)
Digestion system
(Promote secretion of acid)
Metabolism of water and salt
( Increase GFR)
(Glucocorticoids)
(Androgens) (Epinephrine & Norepinephrine)
I Synthesis and Secretion of Adrenocortical Hormones
Adrenocortical Hormones are steroids derived from Cholesterol in distinct cortex ቤተ መጻሕፍቲ ባይዱayers which contain different enzymes.
Cortisol/Hydrocortisone (95%) Corticosterone
Effect on Metabolism (Carbohydrate, Protein & Fat) Resisting Stress Other Effects (Blood and Immunity etc)
Following being secreted into the plasma, adrenocortical hormones binds proteins (such as cortisol-binding globulin, transcortin and albumin)
II Functions of Glucocorticoids
Reduction in Cellular Protein, especially in muscle (Synthesis↓ and Catabolism↑)
Increment in liver and plasma protein
Fat Metabolism
Mobilization of Fatty Acids --- Shift the Cellular Utilization of glucose to fatty acid for energy. (Slow developed but important for long-term conservation of glucose and glycogen) Peculiar Obesity result from Excess Cortisol !!!???