Bhosale K B, Balsara J J, Gaonkar R K, Bhosale B B, Gupta S K
Department of Pharmacology, Krishna Institute of Medical Sciences, Karad, India.
Indian J Exp Biol. 1997 Jun;35(6):618-22.
Metoclopramide (5 to 40 mg/kg, i.p.) induces catalepsy and antagonised apomorphine induced cage climbing behaviour in mice. This further indicate its postsynaptic striatal and mesolimbic D 2 dopamine (DA) receptor blocking activity. Metoclopramide at 1.25 and 2.5 mg/kg, i.p. induced stereotyped cage climbing behaviour in mice. Pretreatment with haloperidol and alpha-methyl-p-tyrosine significantly antagonised metoclopramide (1.25 and 2.5 mg/kg)-induced stereotyped cage climbing behaviour. Metoclopramide at these doses induces stereotyped cage climbing behaviour by releasing DA from the mesolimbic dopaminergic neurons with resultant activation of the postsynaptic mesolimbic D 2 DA receptors by the released DA. DA releasing action of metoclopramide (1.25 and 2.5 mg/kg, i.p.) and the subsequent induction of the stereotyped cage climbing behaviour by these doses of metoclopramide is explained on the basis of selective blockade of the presynaptic D 2 DA autoreceptors by these doses of metoclopramide.
甲氧氯普胺（5至40毫克/千克，腹腔注射）可诱导小鼠出现僵住症，并拮抗阿扑吗啡诱导的小鼠笼内攀爬行为。这进一步表明其具有突触后纹状体和中脑边缘多巴胺D2（DA）受体阻断活性。腹腔注射1.25和2.5毫克/千克的甲氧氯普胺可诱导小鼠出现刻板的笼内攀爬行为。用氟哌啶醇和α-甲基-对-酪氨酸预处理可显著拮抗甲氧氯普胺（1.25和2.5毫克/千克）诱导的刻板笼内攀爬行为。这些剂量的甲氧氯普胺通过从中脑边缘多巴胺能神经元释放DA，使释放的DA激活突触后中脑边缘D2 DA受体，从而诱导刻板的笼内攀爬行为。甲氧氯普胺（1.25和2.5毫克/千克，腹腔注射）的DA释放作用以及这些剂量的甲氧氯普胺随后诱导的刻板笼内攀爬行为，是基于这些剂量的甲氧氯普胺对突触前D2 DA自身受体的选择性阻断来解释的。
