title: Treatment of acute cobalt intoxication in rats with L-methionine.
abstract: The antidotal action of L-methionine in acute cobalt (II) chloride intoxication given orally or intraperitoneally to rats has been investigated in this paper. The doses of CoCl2 (2.73 mmole/kg oral, 0.21 mmole/kg i.p.) are always above their LD50 for both means of administration, reaching during oral administration values above its LD95 (4.20 mmole/kg). The doses of L-methionine varied from 0.63 mmole/kg (i.p.) to 8.19 mmole/kg (orally). L-methionine did not show a significant antidotal action (mortality rates) against the other sulphurous aminoacid: L-cysteine, which is considered an effective antidote. The administration of Co2+-methionine chelates prepared in vitro, showed rates of 10% mortality when given orally and 30% when given intraperitoneally, against Co2+-cysteine and co2+-N-acetylcysteine chelates with rates of 0% mortality. No significant functional changes were observed in the survivors killed seven days after administration in groups receiving L-methionine. Although L-methionine cannot be considered an effective antidote, it is likely to reduce partially the toxic effects of cobalt.
mesh_terms: D000208:Acute Disease; D000284:Administration, Oral; D000818:Animals; D000931:Antidotes / Q000627:therapeutic use*; D003035:Cobalt / Q000008:administration & dosage / Q000633:toxicity*; D003545:Cysteine / Q000627:therapeutic use; D007274:Injections, Intraperitoneal; D007928:Lethal Dose 50; D008297:Male; D008715:Methionine / Q000627:therapeutic use*; D051381:Rats; D011919:Rats, Inbred Strains; D013438:Sulfhydryl Compounds / Q000627:therapeutic use
chemical_list: D000931:Antidotes; D013438:Sulfhydryl Compounds; D003035:Cobalt; D008715:Methionine; C018021:cobaltous chloride; D003545:Cysteine