Toxic effects of cadmium on LHRH-induced LH release and ovulation in rats.
CFY rats were given 5 or 10 mg/kg bw cadmium chloride (CdCl2) or 0.9% NaCl solution (1 mL/kg) subcutaneously on the day of diestrus II. Six days later (proestrus) at 1200 h they were anesthetized with pentobarbital, 0.5 or 2 micrograms/kg LHRH was injected intravenously at 1400 h, and blood was collected for LH determination. A second group of animals pretreated with 10 mg/kg bw CdCl2 and treated with 2 or 4 micrograms/kg LHRH was allowed to recover from the anesthesia and checked for ovulation the next day (estrus). In rats treated with 10 mg/kg of CdCl2, the LH content of pituitary gland diminished, but no significant difference was found in the LH response to LHRH. In controls (ovulation blocked by anesthesia) 2 as well as 4 micrograms/kg of LHRH completely restored ovulation, while after Cd pretreatment, ovulation recovered depending on the dose of LHRH. It is concluded that Cd-induced anovulation is related to altered function of the pituitary gland and ovary, which can be restored by excess LHRH.
Varga
B
B
Department of Experimental Toxicology, National Institute of Occupational Health, Budapest, Hungary.
Paksy
K
K
D000818:Animals; D002104:Cadmium / Q000633:toxicity*; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology*; D007986:Luteinizing Hormone / Q000097:blood / Q000378:metabolism*; D009929:Organ Size / Q000187:drug effects; D010053:Ovary / Q000187:drug effects; D010060:Ovulation / Q000187:drug effects*; D010902:Pituitary Gland / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D002104:Cadmium; D007987:Gonadotropin-Releasing Hormone; D007986:Luteinizing Hormone