title: Action of anti-progesterone monoclonal antibody in blocking pregnancy after postcoital administration in mice.
abstract: Anti-progesterone monoclonal antibody injected intraperitoneally as a single dose 32 h post coitum completely blocked pregnancy in BALB/c and CBA nulliparous mice. The dose required was greater in CBA than in BALB/c females, but in both strains no implantation sites were detectable at autopsy on day 10 after mating. The action of the antibody in BALB/c females was associated with a failure to initiate an implantation response as indicated by the Pontamine Blue reaction. The most pronounced effect, however, was an arrest of embryonic development at a stage prior to cavitation. Plasma progesterone concentration in blood taken by cardiac puncture was greatly increased after treatment, by virtue of high-affinity binding by antibody in circulation. The results show that passive immunization against progesterone shortly after mating interferes with early hormone-dependent steps which are essential for normal embryonic development.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D010064:Embryo Implantation / Q000187:drug effects*; D004622:Embryo, Mammalian / Q000187:drug effects; D005260:Female; D051379:Mice; D008807:Mice, Inbred BALB C; D008808:Mice, Inbred CBA; D010066:Ovum Transport / Q000187:drug effects; D011374:Progesterone / Q000097:blood / Q000276:immunology* / Q000502:physiology; D013997:Time Factors
chemical_list: D000911:Antibodies, Monoclonal; D011374:Progesterone