PANTOTHENOL PROTECTS RATS AGAINST SOME DELETERIOUS EFFECTS OF GAMMA-RADIATION

Rats were exposed to gamma radiation from a Co-60 source, receiving 0. 25 Gy at weekly intervals. During 2 d before each irradiation, the ani mals received daily intragastric doses of 26 mg pantothenol or 15 mg b eta-carotene per kg body weight. One hour after the third irradiation session, the animals were killed and their livers were analyzed. In an imals not supplied with pantothenol, the irradiation resulted in a sig nificant decrease of total liver lipids and a 50% decrease in phosphol ipids. Liver cholesterol was decreased by about 20%. Irradiation produ ced lipid peroxidation as expressed by doubling of the amounts of conj ugated dienes and ketone dienes and of thiobarbituric acid reactive co mpounds. The amount of CoA in liver was decreased by 24% and that of r educed glutathione by 40%. The NAD(+)/NADH ratio was increased by 60% and the activity of NADP-dependent malate dehydrogenase (decarboxylati ng) was decreased by 26%. The amount of pantothenic acid and its deriv atives (expressed as pantolactone-generating compounds) in blood decre ased by about 80%. In rats to which pantothenol was administered, the content of pantothenic acid in blood was tripled compared to nonirradi ated (control) rats, and all the biochemical parameters measured in li ver were the same as in nonirradiated animals. (C) 1998 Elsevier Scien ce Inc.