Operant Performance Following Tail-Pinch in\r\nthe Rat: Effects of d-Amphetamine

Abstract

To extend the investigation of tail-pinch induced behavioral changes, rats performing on a\r\ndifferential reinforcement of low rates of 10 sec (DRL10), a fixed-interval of 60 sec (FI60), and a fixedratio of 20 (FR20) schedules were exposed to a paper clip applied to the tail. While a 10 min tail-pinch\r\nconducted 1 hr before operant sessions significantly altered the DRL10 behavior, this stressor had little\r\neffect on either FI60 or FR20 responding. Marked DRL10 behavior performance changes following tailpinch included increases in the number of lever presses, decreases in the number of the reinforcers, and\r\ndisruption in the frequency distribution of inter-response times (IRT). These DRL10 operant deficits\r\nwere diminished when the subject received a tail-pinch pretreatment followed by d-amphetamine\r\ntreatment (0.2 and 2.0 mg/kg). In combination with biochemical data from others, the present results\r\nsuggest that catecholamine systems are involved in modulation of DRL10 behavior following tailpinch