Glucocorticoids vs. Mineralocorticoids
Glucocorticoids and Mineralocorticoids Definitions
What are Glucocorticoids?
Glucocorticoids (GCs) are the class of hormone secreted by the adrenal cortex; these are corticosteroids which are the class of steroid hormones. The name glucocorticoids are given because (glucose + cortex + steroid) are its basics. They include; Cortisol, Corticosterone, and Cortisone. And their source of secretion is zona fasciculate of the adrenal cortex. These hormones are C21 steroids having 21 carbon atoms in it. The half-life of these hormones are cortisol 70-90 minutes, corticosterone is 50 minutes, and cortisone is not known still. Daily input of cortisol is 10.0 µg, corticosterone is 3.0 µg, and cortisone is still unknown. Glucocorticoids mainly have an effect on the metabolism of glucose via carbohydrate metabolism, protein metabolism, and lipid metabolism. They are thus called as life protecting hormone because they help to withstand stress and trauma in life. Glucocorticoids increase the blood glucose level by two mechanisms, it promotes the process of breakdown of proteins in extrahepatic cells, and it inhibits the uptake of glucose by cells, so they have an anti-insulin effect also. They also cause mobilization and redistribution of fats in the body. Hypersecretion of glucocorticoids may lead to obesity. Others effect of glucocorticoids are, they increase the excretion of water and enhances the retention of sodium, they cause bone resorption (osteoclastic activity) and inhibits bone formation (osteoblastic activity), causes atrophy of muscle due to catabolism of proteins. They also show an essential function on central nervous system (CNS) by facilitating its normal activity. They also have anti-inflammatory and anti-allergic actions. An interesting and specific function of glucocorticoids are seen on blood cells as they increase the count of RBCs, platelets and neutrophils whereas decrease the count of eosinophils, basophils, and lymphocytes.
What are Mineralocorticoids?
Mineralocorticoids are the class of hormone secreted by the adrenal cortex; these are corticosteroids which are the class of steroid hormones. The name mineralocorticoids are given because (minerals + steroid) are its basics. And the source of secretion of mineralocorticoids is zona glomerulosa of the adrenal cortex. These are C21steroids having 21 carbon atoms. The half-life of mineralocorticoids is 20 minutes. Daily output of aldosterone is 0.15 µg, and 11-deoxycorticosterone is 0.2 µg. Mineralocorticoids have the main action on minerals like sodium, potassium and hydrogen ions. These are also called live saving hormone as they maintain the osmolarity and volume of extracellular fluid (ECF) which is a very important factor in life if there is the absence of mineralocorticoids this may lead to sudden death just in 3 day-2 weeks. Mineralocorticoids increase the reabsorption of sodium from renal tubule, causes an increase in excretion of potassium through renal tubule and secretion of hydrogen ions. So, they affect the extracellular fluid (ECF). If there is a reduction in ECF, they increase the reabsorption of sodium along with water reabsorption which results in an increase of ECF. They also cause an increase in blood pressure. Aldosterone have an effect on sweat glands and salivary glands, from here it reabsorbs sodium. The Same effect is seen on intestines of a human.