Behavioral effects of d-amphetamine and apomorphine in the hamster

The effects of d-amphetamine sulfate (0-50 mg/kg) and apomorphine HCl (0-12 mg/kg) on several hamster behaviors were studied. Gnawing, grooming, sniffing, locomoting, circling, rearing, and back arching were measured by direct observation during the period 25-44 min after drug injection. Large doses of d-amphetamine produced significant decreases in grooming and rearing, but significantly increased circling; back arching, sniffing, or gnawing were not affected. Large doses of apomorphine produced significant increases in gnawing and decreases in sniffing, but did not affect grooming, rearing, circling, or back arching. In general, response to either drug was highly variable. The results are discussed in comparison with published data from rats.