Social memory deficits in adult male rats exposed to cadmium in infancy.
In two experiments infant rats were injected subcutaneously with 0, 1, or 2 mg Cd/kg on Day 5 or 6 after birth. In adulthood (150 days of age) subjects in both experiments who received the 2 mg/kg dose failed to learn the identity of a strange rat in a social recognition test. Cadmium-treated rats investigated familiar and strange rats equally, whereas control subjects investigated familiar rats much less than unfamiliar individuals. Results with rats in the 1 mg/kg group were less consistent; in Experiment 1 they failed to learn the identity of a stranger, in Experiment 2 they behaved like controls. The level of investigation of a strange rat did not differ among the experimental groups, indicating cadmium did not cause a performance deficit. The 2 mg/kg dose of cadmium had no effect on body weight in Experiment 1 and a small (6.98%), but significant, depressant effect on body weight in Experiment 2. Cadmium exposure in infancy appears to affect social memory processes long after the treatment period.
Holloway
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Research Department, E.R. Johnstone Training and Research Center, Bordentown, NJ 08505.
Thor
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DH
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002105:Cadmium Poisoning / Q000503:physiopathology / Q000523:psychology*; D008297:Male; D008568:Memory / Q000187:drug effects*; D051381:Rats; D012016:Reference Values; D012919:Social Behavior