Abstract
Depression of conditioned behavior was studied in reserpinized rats before, and 30 minutes after, injections of d- or l-amphetamine. The ability of 0.5 mg/kg d-amphetamine to improve performance was much greater 24 hours after the administration of reserpine than 3 hours afterwards, even though reserpine depression tended to be maximal at 24 hours. The reserpinized rat proved to be more sensitive than control animals to behavioral deficits due to high doses of d-amphetamine. In its ability to antagonize drug-induced depression of behavior, d-amphetamine was about equally effective 3 and 24 hours after fiuphenazine or after urethane, but in neither case was the antagonism as complete as that against reserpine. l-Amphetamine, 0.5 mg/kg, did not significantly alter behavioral depression by reserpine at any time. Higher doses of the l-isomer, 8 mg/kg, presented about the same pattern of antagonism as 0.5 mg/kg d-amphetamine. The low potency of l-amphetamine in antagonizing behavioral depression induced by reserpine, as compared to d-amphetamine, may be related to its lesser potential for releasing brain norepinephrine.
Footnotes
- Accepted September 11, 1964.
- The Williams & Wilkins Comapny
JPET articles become freely available 12 months after publication, and remain freely available for 5 years.Non-open access articles that fall outside this five year window are available only to institutional subscribers and current ASPET members, or through the article purchase feature at the bottom of the page.
|