Detail of "14992-62-2"

Reference

Changes in coenzyme A and carnitine concentrations in superovulated rats

Changes in coenzyme A and carnitine concentrations in superovulated rats. Costa, N. D.; Stevenson, P. M. (Sch. Vet. Stud., Murdoch Univ., Murdoch, WA, USA). Biochim. Biophys. Acta, 792(2), 130-4 (English) 1984. CODEN: BBACAQ. ISSN: 0006-3002. DOCUMENT TYPE: Journal CA Section: 2 (Mammalian Hormones) Section cross-reference(s): 13 The concns. of total CoA [85-61-0], acetyl CoA [72-89-9], free carnitine [541-15-1], and acetylcarnitine [14992-62-2] were measured in ovaries from immature rats before and after superovulation with pregnant mare serum gonadotropin [9002-70-4]. In addn., the concns. of total CoA and total acid-sol. carnitine were measured in liver, adrenal glands, and skeletal muscle from the same rats. Ovarian concns. of total CoA, free carnitine, and acetylcarnitine increased 3-fold on gonadotropin stimulation, whereas there was no marked change in total CoA and acid-sol. carnitine concns. in the other organs. In ovary, the ratio of free CoA to acetyl CoA was about 2:1 during the growth period of follicular development and during active steroidogenesis in the luteal phase, but <1 when replication stopped and ovulation occurred. Total CoA and total acid-sol. carnitine in liver, adrenal glands, and muscle were not affected by the gonadotropin injection. During periods of high energy demand the ovary apparently has a good capacity to accommodate fatty acid oxidn., supporting the evidence that fatty acids are the major source of reducing equiv. for steroidogenesis at these times.

Regulation of palmitate metabolism by carnitine and glucagon in hepatocytes isolated from fasted and carbohydrate refed rats

Regulation of palmitate metabolism by carnitine and glucagon in hepatocytes isolated from fasted and carbohydrate refed rats. Christiansen, Renata Z. (Inst. Med. Biochem., Univ. Oslo, Oslo, Norway). Biochim. Biophys. Acta, 488(2), 249-62 (English) 1977. CODEN: BBACAQ. DOCUMENT TYPE: Journal CA Section: 2 (Hormone Pharmacology) Section cross-reference(s): 13 Glucagon [9007-92-5] stimulated the oxidn. of palmitate [57-10-3] in the liver cells isolated from carbohydrate-refed rats and incubated in a simple salt medium. The maximal stimulation was obsd. at the concn. of glucagon of 4 .times. 10-8M and was noticeable after 5 min of incubation. The stimulation of the oxidn. was balanced mainly by the inhibition of triacylglycerol synthesis. The extent of stimulation was not dependent on the concn. of intracellular carnitine [541-15-1], but was decreased at higher concns. of palmitate in the medium. Glucagon did not have any effect on palmitate metab. in the cells isolated from fasted rats. Under optimal conditions (in the presence of glucagon and an excess of carnitine), the refed cells (cells isolated from livers of rats fasted for 48 h and refed with carbohydrate for 48 h) oxidized palmitate at approx. the same rate as fasted cells (cells isolated from livers of rats fasted for 48 h). However, the refed cells still differed from fasted cells in that they required a much higher intracellular carnitine concn. and a higher palmitate concn. in the medium to reach the maximal level of oxidn. Carnitine decreased the intramitochondrial redox potential in the refed cells which indicated more specific stimulation of .beta.-oxidn. Glucagon increased the redox potential under all conditions used. Glucagon slightly stimulated carnitine transport into the cells and acetylcarnitine [14992-62-2] formation, and had a very pronounced stimulatory effect on synthesis of long-chain acylcarnitines in refed cells. The level of total long-chain acyl-CoA was increased by glucagon in refed cells. Carnitine increased the level of total long-chain acyl-CoA in fasted cells. Apparently, glucagon acts at least in part at 1 of the early stages in fatty acid metab., i.e., carnitine acyltransferase and (or) glycerophosphate acyltransferase.