Your request was heparan which is probably a typo from heparin.
heparan -
Traditional English :: heparin
heparan - n. Biochem. a substance produced in liver cells etc. which inhibits blood coagulation, and is used as an anticoagulant in the treatment of thrombosis.
heparinize v.tr. (also -ise). [L f. Gk hepar liver]