Stored triacyl glycerol and cholesterol are released by
|D||Hormone sensitive lipase|
Hormone sensitive Lipase: -
a. Adipose tissue is the main store of Triacyl glycerol in the body.
b. These Triacyl-glycerol undergoes hydrolysis by the Hormone-sensitive lipase to form fatty acid and
c. This Hormone sensitive lipase is activated by ↑cAMP→Epinephrine, norepinephrine, glucagon, ACTH, MSH, TSH, GH, and vasopressin. For optimal effect most of these lipolytic processes require the presence of glucocorticoids and thyroid hormones.
4. This lipase is inhibited by ‘insulin, PG E and nicotinic acid;.
Lipoprotein Lipase: - LPL: -
a. Triacylglycerol of chylomicrons and VLDL are hydrolyzed by LPL.
b. LPL is located in the wall of blood capillaries, anchored to endothelium, by negatively. charged Heparin sulfate.
c. It is found in Heart, Adipose tissue, spleen, lungs, renal medulla, Aorta, diaphragm, Lactating mammary glands and Neonatal Liver not found in Adult liver.
d. Following injection of “ LPL is released from endothelium into circulation and is accompanied by the clearing of Lipemia.
e. Insulin enhances its synthesis in Lipocytes.
f. 6. Chylomicron remnants formed after action of LPL on chylomicron are enriched in cholesterol, and cholesteryl ester because of loss Tri acyl-glycerol 90% loss.