Activation of 5-HT1B receptors in the nucleus accumbens reduces amphetamine-induced enhancement of responding for conditioned reward

被引：0

作者：

Paul J. Fletcher

Karin M. Korth

机构：

[1] Department of Psychology,

[2] University of Toronto,undefined

[3] 250 College Street,undefined

[4] Toronto,undefined

[5] Ontario,undefined

[6] Canada M5T 1R8,undefined

[7] Department of Psychiatry,undefined

[8] University of Toronto,undefined

[9] 250 College Street,undefined

[10] Toronto,undefined

[11] Ontario,undefined

[12] Canada M5T 1R8,undefined

[13] Section of Biopsychology,undefined

[14] Centre for Addiction and Mental Health,undefined

[15] Clarke Division,undefined

[16] 250 College Street,undefined

[17] Toronto,undefined

[18] Ontario,undefined

[19] Canada M5T 1R8 e-mail: fletcher@psych.utoronto.ca,undefined

[20] Fax: +1-416-979-6942,undefined

来源：

Psychopharmacology | 1999年 / 142卷

关键词：

Key words 5-Hydroxytryptamine; 5-HT1B receptor; Nucleus accumbens; d-Amphetamine; Conditioned reward; Dopamine;

D O I：

暂无

中图分类号：

学科分类号：

摘要：

Previously, we have demonstrated that 5-hydroxytryptamine (5-HT) injected into the nucleus accumbens attenuates the potentiating effects of d-amphetamine on responding for conditioned reward (CR). The present studies examined the 5-HT receptor involved in this effect by investigating the effects of 5-HT agonists with differing affinities for 5-HT1 and 5-HT2 receptors on d-amphetamine-induced potentiation of responding for CR. Rats were trained to associate a light/tone stimulus (subsequently the CR) with water delivery. In a test phase, they were allowed access to a lever delivering the CR, and an inactive (NCR) lever. Responding on the CR lever was greater than responding on the NCR lever, indicating that the light/tone stimulus functioned as a CR. Responding for the CR was selectively potentiated by injections of d-amphetamine (10 μg) into the nucleus accumbens. This effect was reduced by injections into the nucleus accumbens of 5-CT (0.5 and 1 μg), RU24969 (10 μg), CP93,129 (1.25 and 2.5 μg) but not by DOI (10 μg) or 8-OH-DPAT (5 μg). The lower doses of 5-CT and CP93,129 did not reduce baseline responding for CR, or responding for water in a separate group of animals, indicating that the effects of these drugs were behaviourally selective. The higher doses abolished the CR effect, and in the case of 5-CT and RU24969 also reduced responding for water. All of the effective drugs share in common the ability to stimulate 5-HT1B receptors, albeit with differing selectivities. The effect of CP93,129, the most selective of the 5-HT1B agonists, to inhibit the response-potentiating effect of d-amphetamine was reversed by the5-HT1B/1D antagonist GR127935 (3 mg/kg). The results indicate that activation of 5-HT1B receptors within the nucleus accumbens attenuates the effects of a dopamine-dependent behaviour, and that activation of these receptors can oppose the behavioural effects of elevated mesolimbic dopamine transmission.

引用

页码：165 / 174

页数：9