Methylphenidate-induced conditioned taste aversions: An index of toxicity

Abstract

Following consumption of saccharin, groups of rats were injected with various doses of methylphenidate hydrochloride. Small aversions were found after one conditioning trial, with repeated saccharin-methlyphenidate pairings resulting in continued decrements in consumption. The strength of the aversion as well as the amount of individual variability were doserelated, with weaker aversions and greater individual variability occurring at the smaller dose (15 mglkg). Although aversions were quite pronounced at higher doses, individual variability, although small, was still evident. The similarities and differences between methylphenidate-induced aversions and aversions based on emetics were discussed, along with the implications of these results as indices for methylphenidate-induced toxicity.

Effect of age on methylphenidate-induced conditioned taste avoidance and related BDNF/TrkB signaling in the insular cortex of the rat

“…The present study evaluated age effects in CTA induced by MPH in adolescent and adult animals. In accordance with previous research, MPH induced robust taste avoidance of saccharin (Riley and Zellner 1978;Wetzell and Riley 2012), and in support of our hypothesis, the effect was attenuated in adolescent animals compared to adults. Adolescents were generally slower to acquire avoidance, as none of the MPH groups suppressed consumption until trial 3, while all three of the adult MPH groups had done so by trial 2.…”

“…Additionally, both adolescent and adult rats self-administer MPH (dela Peña et al 2011), with no direct age comparisons reported. MPH produces dosedependent CTA in adult animals (Riley and Zellner 1978;Wetzell and Riley 2012), and since adolescents display attenuated CTA to other psychostimulants, it is reasonable to expect that the same will be true for MPH. Such a result could indicate an enhanced abuse potential for MPH in adolescents and should be examined further.…”