Disposition of [s]-heparin in the rat.

[(35)S]-Heparin is rapidly taken up by tissues after intraperitoneal injection andrapidly degraded. Skin, aorta and lung showed an especially high affinity for[(35)S]-heparin. In these organs, as well as in adrenal gland, stomach, heart and brain,the isotope was found preponderantly as dialysable metabolite(s) of heparin. Another group of tissues (large intestine, fat, kidney and liver) was characterized by a smaller proportion of dialysable material. Tissues that showed a high affinity for exogenous heparin appeared to catabolize it rapidly. It is also noted that some of the radioactive material present in tissues after the injection of [(35)S]-heparin could come from the uptake of [(35)S]-sulphate resulting from the degradation of [(35)S]-heparin. The incorporation of [(35)S]-sulphate into the sulphomucopolysaccharides of some tissues is recorded.