title: Long-acting delivery systems for peptides: inhibition of rat prostate tumors by controlled release of [D-Trp6]luteinizing hormone-releasing hormone from injectable microcapsules.
abstract: Intramuscular injection of [6-D-tryptophan]-luteinizing hormone-releasing hormone [( D-Trp6]LH-RH) in microcapsules of poly(DL-lactide-co-glycolide), designed to release a controlled dose of the peptide over a 30-day period, decreased the weights of androgen-dependent Dunning prostate tumors in rats and suppressed serum testosterone levels more effectively than daily subcutaneous administration of equivalent or double doses of unencapsulated [D-Trp6]LH-RH. The microcapsules or daily injections of [D-Trp6]LH-RH also significantly decreased tumor volumes. Microcapsules of [D-Trp6]LH-RH or related analogs that can be injected once a month should make the treatment of patients with prostate carcinoma and other neoplasms or disorders more convenient and efficacious.
mesh_terms: D000818:Animals; D002460:Cell Line; D003692:Delayed-Action Preparations; D007987:Gonadotropin-Releasing Hormone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D008186:Luteolytic Agents / Q000627:therapeutic use*; D008297:Male; D008855:Microscopy, Electron, Scanning; D011471:Prostatic Neoplasms / Q000188:drug therapy*; D051381:Rats; D011919:Rats, Inbred Strains; D017329:Triptorelin Pamoate
chemical_list: D003692:Delayed-Action Preparations; D008186:Luteolytic Agents; D017329:Triptorelin Pamoate; D007987:Gonadotropin-Releasing Hormone