Biomaterial Database

Plasma lecithin:cholesterol acyltransferase activity in hypophysectomized rats. 1978

V Manninen, and M Mälkönen, and J P Blomhoff, and E Gjone

Hypophysectomy in rats induces a decrease in VLDL and HDL and an increase in LDL. To investigate the importance of lecithin:cholesterol acyltransferase (LCAT) for these changes, plasma LCAT activity was determined, both according to the methods of Stokke-Norum and Glomset-Wright. Plasma LCAT activity as assessed by both these methods decreased significantly after hypophysectomy, indicating a reduction in plasma enzyme concentration. Plasma total and free cholesterol increased slightly, while the concentration of cholesteryl esters and triglycerides remained unchanged. Blood sugar and FFA decreased. The osmotic resistance of the red cells was increased, and target cells were seen. There was a decrease in blood haemoglobin and haematocrit. Serum total protein concentration, electrophoresis, and plasma ALAT activity did not change. The observed changes in lipoproteins and LCAT following hypophysectomy can be partly explained by decreased liver secretion of both LCAT and VLDL. Because of the complex relationship between lipoproteins and LCAT, no clear-cut conclusions about the association between decreased HDL and LCAT can be drawn. The precise hormonal mechanisms controlling LCAT activity and lipoprotein metabolism remain to be solved.

UI	MeSH Term	Description	Entries
D007016	Hypophysectomy	Surgical removal or destruction of the hypophysis, or pituitary gland. (Dorland, 28th ed)	Hypophysectomies
D007862	Phosphatidylcholine-Sterol O-Acyltransferase	An enzyme secreted from the liver into the plasma of many mammalian species. It catalyzes the esterification of the hydroxyl group of lipoprotein cholesterol by the transfer of a fatty acid from the C-2 position of lecithin. In familial lecithin:cholesterol acyltransferase deficiency disease, the absence of the enzyme results in an excess of unesterified cholesterol in plasma.	Lecithin Cholesterol Acyltransferase,Cholesterol Ester Lysolecithin Acyltransferase,Lecithin Acyltransferase,Phosophatidylcholine-Sterol Acyltransferase,Acyltransferase, Lecithin,Acyltransferase, Lecithin Cholesterol,Acyltransferase, Phosophatidylcholine-Sterol,Cholesterol Acyltransferase, Lecithin,O-Acyltransferase, Phosphatidylcholine-Sterol,Phosophatidylcholine Sterol Acyltransferase,Phosphatidylcholine Sterol O Acyltransferase
D008075	Lipoproteins, HDL	A class of lipoproteins of small size (4-13 nm) and dense (greater than 1.063 g/ml) particles. HDL lipoproteins, synthesized in the liver without a lipid core, accumulate cholesterol esters from peripheral tissues and transport them to the liver for re-utilization or elimination from the body (the reverse cholesterol transport). Their major protein component is APOLIPOPROTEIN A-I. HDL also shuttle APOLIPOPROTEINS C and APOLIPOPROTEINS E to and from triglyceride-rich lipoproteins during their catabolism. HDL plasma level has been inversely correlated with the risk of cardiovascular diseases.	High Density Lipoprotein,High-Density Lipoprotein,High-Density Lipoproteins,alpha-Lipoprotein,alpha-Lipoproteins,Heavy Lipoproteins,alpha-1 Lipoprotein,Density Lipoprotein, High,HDL Lipoproteins,High Density Lipoproteins,Lipoprotein, High Density,Lipoprotein, High-Density,Lipoproteins, Heavy,Lipoproteins, High-Density,alpha Lipoprotein,alpha Lipoproteins
D008077	Lipoproteins, LDL	A class of lipoproteins of small size (18-25 nm) and light (1.019-1.063 g/ml) particles with a core composed mainly of CHOLESTEROL ESTERS and smaller amounts of TRIGLYCERIDES. The surface monolayer consists mostly of PHOSPHOLIPIDS, a single copy of APOLIPOPROTEIN B-100, and free cholesterol molecules. The main LDL function is to transport cholesterol and cholesterol esters to extrahepatic tissues.	Low-Density Lipoprotein,Low-Density Lipoproteins,beta-Lipoprotein,beta-Lipoproteins,LDL(1),LDL(2),LDL-1,LDL-2,LDL1,LDL2,Low-Density Lipoprotein 1,Low-Density Lipoprotein 2,LDL Lipoproteins,Lipoprotein, Low-Density,Lipoproteins, Low-Density,Low Density Lipoprotein,Low Density Lipoprotein 1,Low Density Lipoprotein 2,Low Density Lipoproteins,beta Lipoprotein,beta Lipoproteins
D008079	Lipoproteins, VLDL	A class of lipoproteins of very light (0.93-1.006 g/ml) large size (30-80 nm) particles with a core composed mainly of TRIGLYCERIDES and a surface monolayer of PHOSPHOLIPIDS and CHOLESTEROL into which are imbedded the apolipoproteins B, E, and C. VLDL facilitates the transport of endogenously made triglycerides to extrahepatic tissues. As triglycerides and Apo C are removed, VLDL is converted to INTERMEDIATE-DENSITY LIPOPROTEINS, then to LOW-DENSITY LIPOPROTEINS from which cholesterol is delivered to the extrahepatic tissues.	Pre-beta-Lipoprotein,Prebeta-Lipoprotein,Prebeta-Lipoproteins,Very Low Density Lipoprotein,Very-Low-Density Lipoprotein,Very-Low-Density Lipoproteins,Lipoprotein VLDL II,Lipoproteins, VLDL I,Lipoproteins, VLDL III,Lipoproteins, VLDL1,Lipoproteins, VLDL2,Lipoproteins, VLDL3,Pre-beta-Lipoproteins,Lipoprotein, Very-Low-Density,Lipoproteins, Very-Low-Density,Pre beta Lipoprotein,Pre beta Lipoproteins,Prebeta Lipoprotein,Prebeta Lipoproteins,VLDL Lipoproteins,VLDL1 Lipoproteins,VLDL2 Lipoproteins,VLDL3 Lipoproteins,Very Low Density Lipoproteins
D002784	Cholesterol	The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.	Epicholesterol
D002788	Cholesterol Esters	Fatty acid esters of cholesterol which constitute about two-thirds of the cholesterol in the plasma. The accumulation of cholesterol esters in the arterial intima is a characteristic feature of atherosclerosis.	Cholesterol Ester,Cholesteryl Ester,Cholesteryl Esters,Ester, Cholesterol,Ester, Cholesteryl,Esters, Cholesterol,Esters, Cholesteryl
D005230	Fatty Acids, Nonesterified	FATTY ACIDS found in the plasma that are complexed with SERUM ALBUMIN for transport. These fatty acids are not in glycerol ester form.	Fatty Acids, Free,Free Fatty Acid,Free Fatty Acids,NEFA,Acid, Free Fatty,Acids, Free Fatty,Acids, Nonesterified Fatty,Fatty Acid, Free,Nonesterified Fatty Acids
D005260	Female		Females
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia