Summary
Metabolism and kinetics of 3H-heparin were compared in intact and hepatectomized rats. Rats were divided into
three groups: 1) intact rats with biliary fistulas and cystostomies 2) intact rats
with only cystostomies and 3) hepatectomized rats with cystostomies. Radioactivity
in blood, bile and urine besides anticoagulant activity in blood and urine were examined.
In addition, column chromatography of urine was used to isolate possible metabolites.
Seventy percent and 80% of the radioactive dose was found in the urine of intact rats
at 24 hr and 48 hr. Close to 5% of the radioactivity was found in bile or rats with
a biliary fistula after 48 hr. The APTT declined to near normal values at 1 hr whether
rats had a biliary fistula or not. In contrast, only 25 % of the radioactivity could
be excreted into the urine of hepatectomized rats in 24 hr; the APTT did not decline
as fast and at 5 hr, it was still 100 seconds. Only one radioactive component could
be isolated on chromatography from all urines of these animals and appears to be similar
to the original heparin. Thus, the liver has an important role to play in regulating
the anticoagulant effects and excretion of heparin.
Keywords
Heparin - Hepatectomy - APTT - Excretion