Narayanan S, Willins D, Dalia A, Wallace L, Uretsky N
Division of Pharmacology, College of Pharmacy, Ohio State University, Columbus 43210, USA.
Pharmacol Biochem Behav. 1996 Jul;54(3):565-73. doi: 10.1016/0091-3057(95)02220-1.
The bilateral administration of 10 micrograms of (+)MK-801, but not (-)MK-801, into either the VTA or the N.Ac. stimulated locomotor activity. The stimulation induced by (+)MK-801 at both sites was inhibited by reserpine (5 mg/kg, SC) and the D1 antagonist, SCH 23390 (0.1 mg/kg, SC). Eticlopride (0.03 mg/kg, SC), a D2 antagonist, inhibited the stimulation produced by MK-801 in the VTA but not in the N.Ac. Baclofen (32 ng), a GABAB receptor agonist, injected into the VTA inhibited the stimulatory response to MK-801 injected systemically, into the VTA, or into the N.Ac., but did not significantly inhibit spontaneous locomotion or the stimulatory response to apomorphine (5 mg/kg, SC). These observations suggest that the stimulatory effects of MK-801 in the VTA and the N.Ac. are dependent on endogenous dopamine. In addition, the effects produced by MK-801 injected into the VTA closely resemble those produced by the systemic administration of low doses of MK-801, suggesting that this is the primary site of action of MK-801.
向腹侧被盖区（VTA）或伏隔核（N.Ac.）双侧注射10微克（+）MK - 801可刺激运动活性，但注射（-）MK - 801则无此作用。（+）MK - 801在这两个部位所诱导的刺激作用均被利血平（5毫克/千克，皮下注射）和D1拮抗剂SCH 23390（0.1毫克/千克，皮下注射）抑制。D2拮抗剂阿立必利（0.03毫克/千克，皮下注射）抑制了MK - 801在VTA产生的刺激作用，但对在N.Ac.产生的刺激作用无抑制效果。GABAB受体激动剂巴氯芬（32纳克）注射到VTA中，抑制了对全身注射、注射到VTA或N.Ac.的MK - 801的刺激反应，但未显著抑制自发运动或对阿扑吗啡（5毫克/千克，皮下注射）的刺激反应。这些观察结果表明，MK - 801在VTA和N.Ac.中的刺激作用依赖于内源性多巴胺。此外，注射到VTA中的MK - 801所产生的作用与低剂量MK - 801全身给药所产生的作用非常相似，这表明VTA是MK - 801的主要作用部位。
