title: Effect of removal of carbohydrate residues upon the half life and in vivo biological activity of human chorionic gonadotropin.
abstract: The effect of progressive enzymatic removal of various carbohydrates on the half life (T 1/2) and biologic activity in vivo of hCG was studied in rats. The cleavage of carbohydrates such as galactose, glucosamine and mannose, in addition to sialic acid, reduced the T 1/2 from 60--90 for native hCG to less than 3 minutes. The hCG derivatives had no inherent ability to cause ovulation, but in PMSG, Nembutal-treated immature rats, the hCG derivatives with carbohydrate residues internal to sialic acid removed blocked the stimulatory effect of native hCG upon ovulation.
mesh_terms: D000818:Animals; D002241:Carbohydrates / Q000502:physiology; D006063:Chorionic Gonadotropin / Q000378:metabolism* / Q000494:pharmacology; D005260:Female; D008657:Metabolic Clearance Rate; D009865:Oocytes / Q000187:drug effects; D010060:Ovulation / Q000187:drug effects; D051381:Rats; D013329:Structure-Activity Relationship; D014018:Tissue Distribution; D014599:Uterus / Q000187:drug effects
chemical_list: D002241:Carbohydrates; D006063:Chorionic Gonadotropin