Effects of Ginseng on the Metabolism of Enflurane and Methoxyflurane

Ginseng has been believed to be a powerful tonic by oriental people for a long time and is one of the most popular folk medicine in oriental countries. Intraperitoneal injection of ginseng into rats and mice has been reported to Increase the rates of hepatic RNA and protein synthesis, increase proliforation of rough RES of liver, and enhance alcohol metabolism. We have carried out a study to see the effects of red ginseng powder and extract on in vivo and in vitro metabolism of enflurane and methoxyflurane in male Fisher 344 rats. Red ginseng powder was dissolved in deionized water and dosed for two weeks ad libitum in rats. Hepatic microsomes were prepared and oxidative defluorination of enflurane and methoxyflurane were measured in vitro. Using red ginseng extract, studies were done of both acute and chronic treatment in rats. In chronic experiments, they were dosed with several dosages three times a day for three days; on the fourth day enflurane was administered i.p. and one hour later fluoride levels were mesured in plasma and hepatic microsomes were prepared for in vitro studies as above. In the acute experiment enflurane was administered intraperitoneally eighteen hours after single oral dosage of ginseng and plasma defluorination was measured. There were no statistically significant differences in hepatic microsomal cytochrome P-450 content or defluorination of enflurane and methoxyflurane between control and experimental groups using either red ginseng extract or powder. The results showed that ginseng ingestion did not affect the metabolism of enflurane and methoxyflurane.

Biotransformaçäo relacionada à toxicidade de anestésicos inalatórios / Biotransformation related to toxicity of inhaled anesthetics

Säo apresentados alguns conceitos básicos sobre o metabolismo das drogas anestésicas, no que concerne à biodisponibilidade e à bioestabilidade, assim como as reaçöes que ocorrem no organismo, classificadas em Reaçöes da Fase I (oxidaçäo, reduçäo e hidrólise) e Reaçöes da Fase II (síntese). Alguns conceitos sobre a induçäo enzimática säo mostrados, com destaque para o complexo do citocromo P-450. A metabolizaçäo dos anestésicos inalatórios: halotano, metoxiflurano, enflurano e isoflurano: a produçäo de metabólitos importantes na toxicidades destes agentes, especialmente para o fígado e rins säo revistos, bem como as possíveis implicaçöes clínicas que podem advir destes metabólitos. Informaçöes sobre medidas profiláticas säo dadas. O metoxiflurano está em desuso, a sua nefrotoxicidade torna-se pouco importante A nefrotoxicidade devido ao enflurano e isoflurano é improvável, pela sua pequena taxa de metabolizaçäo. Com relaçäo à toxicidade hepática, apenas o halotano tem merecido maiores investigaçöes