THE ADRENAL GLAND

The Adrenal Gland

The Adrenal Gland

The adrenal medulla catecholamine

The adrenal cortex corticoids

Anatomy of Adrenal Cortex

zona glomerulosa secretes aldosterone

zona fasciculata secretes glucocorticoids

zona reticularis secretes androgens

Adrenocortical hormone

Renal and Circulatory effects of Aldosterone

Aldosterone Increases Renal Tubular Reabsorption of Na+ and Secretion of K+ Excess Aldosterone↑→ ECF ↑→ABP↑ Small effect on plasma Na+ Concentration

Renal and Circulatory effects of aldosterone

K+ concentration Aldosterone ↑→ Hypokalemia and Muscle

Weak-ness Aldosterone ↓→Hyperkalemia and Cardiac

Toxicity Mild Alkalosis: Aldosterone ↑ adrenal glands suddenly stop secreting

aldosterone salt are lost in the urine→ECF↓ → blood volume

↓ → circulatory shock → causes death within a few days (without treatment)

Glucocorticoids

Function

:inhibit NADH oxidation which is necessary for glycolysis

:FFA↑

Glucocorticoids

Function

Poor wound healing

not most other cells

Glucocorticoids

Function

: same with mobilization of amino acid from muscle glucose uptake in adipose cell ↓

Glucocorticoids

Function

Cushing’s syndrome

Cushing’s syndrome

Buffalo-like torso Rounded face, “moon-face”.

Glucocorticoids

Function Resisting stress

Trauma , infection, intense heat or cold, surgery

Resisting stress

stressor

Brain

Anterior pituitary (ACTH) Sympathetic nervous system

Adrenal cortex Adrenal medulla

Glucocorticoids NE,E

Glucocorticoids

Function

Glucocorticoids

Function

Summary of glucocoticoid action

Gs Hepatic gluconeogenesis↑Insulin action↓

BG ↑ Glucocoticoid↑→Adrenal diabetes

Pro-tein

Catabolism ↑ (especially in muscle)anabolism ↓

Amino acid in blood plasma

difficult of wound healing

Fat Fat mobilization ↑Fat redistribution

acetone body ↑ Glucocoticoid↑→central obesityCushing’s syndrome

H2O and Na+

Similar with aldosteroneADH ↓GFR ↑

(1/400 of aldosterone)

Glucocoticoid↓→Water Intoxication

Blood cell

hematopoiesis↑lymphopoiesis↓lung and spleen eosinophil storage↑

RBC↑TBC↑lymphocyte↓neutrophil↑eosinophil ↓

Leuke-mia

Gastric shield

gastric acid and peptic enzyme ↑gastric mucosa↓fall off of gastric epithelia cell

ulcer ↑

Circulat-ion

permisivienesss

glucocoticoid↓→BP↓

CNSexcitability↑

less→euphoriamore→restlessness,insomnia

Regulation of Secretion of Adrenocortical Hormone

Hypothalamus – Anterior Pituitary – Adrenocortical Axis

Regulation of Secretion of Adrenocortical Hormone

Action of CRH Synthesis and release of ACTH

Action of ACTH (adrenocorticotropin hormone ) control Cortisol secretion hypertrophy and proliferation of

the adrenocorticol cells

Large amount administration of exogenous glucocoticoid , prohibit to stop using it suddently

?

Regulation of Secretion of Adrenocortical Hormone

Regulation of cortisol Secretion Negative feedback

effect of cortisol

Diseases of Adrenal Glands

Cushing’s Disease Hyper-active adrenal cortex rounded face & obesity Thin, frail skin poor wound healing

Addison’s Disease Hypo-active adrenal cortex Decreased appetite, weight loss Cold intolerance Stress susceptibility

The adrenal medulla

The adrenal medulla

The adrenal medulla

The adrenal medulla

Insulin

Insulin Small protein

51 AA Receptor

Tyrosine kinase

Insulin

Insulin

acetoacetic acid is also converted into b-

hydroxybutyric acid and acetone.

ketone bodies: Acetoacetic, b-hydroxybutyric acid ,acetone

Insulin

Insulin

Glucagon

Endocrine regulation of calcium and phosphate metabolism

Parathyroid hormone (PTH)

Polypeptide

Parathyroid hormone (PTH)

Funtion : increase the calcium concentration Bone

Stimulate osteoclast to remove Ca 2+ from the bone matrix

Kidney: Increased Ca2+ reabsorption, PO4

2- excretion Small intestine

Increased Ca2+ reabsorption

Parathyroid hormone (PTH)

Calcitonin

Produced by the C cells of the thyroid gland.

Function plasma Ca 2+ and PO4

2-↓

Regulation Concentration of Ca 2+ increased ,The

calcitonin increased.

Vitamin D3

Function ↑intestinal calcium and phosphate

absorption. ↓renal calcium and phosphate excretion. Coordinate with PTH increase Ca 2+ .

Summary

Summary