Inhibition of pituitary-gonadal axis in mice by long-term administration of D-Trp-6-LHRH microcapsules.
Female mice were injected, every 30 days for 5 months, with a long-acting formulation of microcapsules liberating 2.5 micrograms D-Trp-6-LHRH/day. The control group was injected with vehicle only. At 30 days after the last injection mice were killed, ovaries, uteri and adrenals were weighed and fixed in formalin for histological studies. LH and oestradiol concentrations were measured by RIA. In the D-Trp-6-LHRH-treated group, the weights of the ovaries and uterus (P less than 0.01 and P less than 0.05, respectively), and LH and oestradiol values (P less than 0.02 and P less than 0.01, respectively) were reduced compared to controls. Histologically, the ovaries contained a large number of degenerated, atretic follicles, and corpora lutea had almost completely disappeared. These results indicate, contrary to the prevailing opinion, that mice are sensitive to inhibitory effects of LHRH agonists and that a suppression of the pituitary-gonadal axis can be obtained with long-term administration of D-Trp-6-LHRH microcapsules.
Bokser
L
L
Department of Medicine, Tulane University School of Medicine, New Orleans, LA 70112.
Zalatnai
A
A
Schally
A V
AV
D000818:Animals; D002214:Capsules; D004958:Estradiol / Q000097:blood*; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D007986:Luteinizing Hormone / Q000097:blood*; D008186:Luteolytic Agents / Q000008:administration & dosage; D051379:Mice; D009929:Organ Size / Q000187:drug effects; D010053:Ovary / Q000033:anatomy & histology / Q000187:drug effects*; D013997:Time Factors; D017329:Triptorelin Pamoate; D014599:Uterus / Q000033:anatomy & histology / Q000187:drug effects
D002214:Capsules; D008186:Luteolytic Agents; D017329:Triptorelin Pamoate; D007987:Gonadotropin-Releasing Hormone; D004958:Estradiol; D007986:Luteinizing Hormone