BY

MOHAMMAD AMIN

(M.Sc Clinical Biochemistry)

UNIVERSITY OF KASHMIR ..

ameendelina@gmail.com

The adrenal gland are paired organs present on both kidneys consisting of both cortex and medulla which differ intheir structure and function

The adrenal cortex mainta-ins the E C F, blood volume ,ionic concen-tration ,glucose and fat metabolism and plays major role in foetal development till puberty for development of gonads

Zone of glomerulosa... Secretes minerocorticoids

zone of fasciculata..... Secretes glucocorticoids

Zone of reticularis....secretes androgens

Steroid harmones are produced from adrenal cortex from choletrol

LDL in plasma containing high concentration of cholestrol provides 80% of cholestrol and attach on coated pits

Entered cholestrol is delivered to mitochondria where it is cleaved by enzyme cholestrol DESMOLASE

This step depends on feedback mechanism for conversion of cholestrol to pregnenolone.

CHOLESTROL

PREGNENOLONE

PROGESTERONE

11 DEOXYCORTICOSTERON E

CORTICOSTERONE

ALDOSTERONE

17 HYDROXYPREGNENOLONE

17 HYDROXYPROGESTERONE

11 DEOXYCORTISOL

Cortisol

DehydroeplanDrosterone

Androstenedione

Testosterone

DESMOlASE

3βHSD

21 HYDROXYLASE

11 βHYDROXYLASE

ALDOSTERONE SYNTHASE

17 αHYDROXYLASE LYASE

LYASE

3βHSD

17βHSD

MINERALCORTICOID .15mg/day GLUCOCORTICOIDS 20mg/day

MINERALCORTICOID example aldosterone.....increases absorption of sodium and simultaneously increases secretion of potassium by renal tubular epithelial cells

The absorption of sodium causes osmotic pressure change and cause water to enter if present if less level of water is present it causes thirst stimulation

Increase in extracellular fluid volume ultimately cause increase in arterial pressure

The increase in arterial pressure causes excreation of salt water i.e pressure natriuresis and pressure diuresiscalled ALDOSTERONE ESCAPE

The aldosterone when enters in cell cytoplasm combines with highly receptor protein that will ultimately form m RNA to the process of sodium and potassium transport.

The diffusion of RNA into cytoplasm cause formation of membrane transport protein for exchange of sodium potassium and hydrogen through cell in renal tubules.

Increased potassium ion concentration in the extracellular fluid increases aldosteronesecretion

Increased activity of renin angiotensin system also increases aldosterone secretion

Increased sodium level in E.C.F ACTH has low effcet to release aldosterone

Glucocorticoids released from zone of fasciculata which helps in carbohydrate ,protein and fat metabolism.

Carbohydrate metabolism Glucocorticoids cause stimulation of gluconeogenesis i.e

formation of carbohydrate from protein and some other substances by liver

Mobilization of amino acids from muscles to cause more gluconeogenesis

Protein metabolism Reduction of protein stores in all parts of body except liver

which is caused by cortisol [increased catabolism of protein]

The increased amino acid from muscle cells cause increase in synthesis of plasma protein from hepatic cells in liver.

Fat metabolism Cortisol enhances the oxidation of fatty acids in the cell hence

cause fat mobilization which helps in shift the metabolic system of cells utilization of glucose for energy to utilize fats in times of starvation or other stresses

RESULTS UNKNOWN FOR INCREASE IN RED CELLS AND DECREASE IN IMMUNE CELLS

The excess cortisol secretion by adrenal gland cause polycythemia and also when adrenal gland secrets no cortisolcause anemia

The T cells and antibodies release from lymphoid tissue is decreased due to cortisol secretion from adrenal gland hence decrease in immunity but ability of cortisol to suppress immunity which acts as a drug in preventing immunological rejection of transplanted hearts ,kidney etc

ACTH also called corticotropin or adrenocorticotropin harmone secreted by anterior pituatry which is controlled by releasing factor of hypothalamus [corticotropin releasing factor CRF].The ACTH cause activation of adenylcyclase in adrenal cells which cause formation of CAMP

Which cause activation of protein kinase which causes conversion of cholestrol to pregnenolonewhich regulates synthesis of adrenocorticoidharmones

Androgens are sex harmones which are secreted from zone of reticularis like dehydroepiandrosterone, progesterone and estrogen etc

Secretes during fetal development, sexual organ development and secondary sexual characteristics

Testosterone cause descent of testis in scrotum Hypertrophy of laryngeal mucosa and develops

masculine voice Testosterone cause protein formation and there

deposition in the skin which causes muscle development

Estrogen is released in females and progestrone cause mantainance of pregnancy in females