Production of labelled 25 hydroxyvitamin D from 14C vitamin D as a marker of liver function after 65 per cent hepatectomy in dogs

Abstract

In order to appreciate hepatocyte activity after 65 per cent hepatectomy, plasma 14C 25-hydroxyvitamin D ( 14C 25-OH-D, % total dose x litre −1x body weight-kg-) was measured following an intraportal bolus injection of 4 μCi 14C vitamin D. As disturbance of the spleno-pancreatic venous flow might lead to post operative hepatic atrophy, the hepatectomized dogs were separated into three groups: no shunt (group I, n=8), mesocaval (group II, n=3) or portocaval shunt (group III, n=8). As compared with five controls, the 14C 25-OH-D level at day 6 was within the normal range (mean ± SEM = 231±21) in groups I (187±28) and II (184±12) and was significantly depressed in group III (114±14, p<0.01). The results were compared with post operative proaccelerin levels, which were decreased in group III (61±9%) and normal (100%) in the other groups. From the present results, it appears that 25 hydroxylation is a reliable index of liver function and that portacaval shunts impair liver activity after 65 per cent hepatectomy. The latter finding could result either from a major reduction in hepatic blood flow or suppression of such hepatotrophic factors as pancreatic hormones.