Dallimore Jeanine E, Mickiewicz Amanda L, Napier T Celeste
Department of Pharmacology and Experimental Therapeutics, Loyola University Chicago, School of Medicine, Maywood, IL 60153-5515, USA.
Behav Neurosci. 2006 Oct;120(5):1103-14. doi: 10.1037/0735-7044.120.5.1103.
The role of ionotropic glutamate receptors within the ventral pallidum (VP) in the expression of conditioned place preference (CPP) and motor adaptations to morphine was evaluated. VP-cannulated rats were subjected to 3 days of conditioning in which saline was paired to one distinct chamber in the morning and morphine (8 mg/kg ip or its vehicle) was paired to an alternate chamber in the afternoon. This induced (a) CPP expression in drug-free rats 1 day later, which was blocked by immediate pretreatments with intra-VP injections of a glutamate antagonist cocktail (DL-2-amino-5- phosphonopentanoic acid lithium salt [AP-5] + 6-cyano-7-nitroquinoxaline-2,3-dione disodium salt [CNQX]), and (b) changes in motor function expressed following an acute morphine challenge 18 days later, which were absent if preceded by a 10-day treatment with the glutamate antagonists injected unilaterally once daily in alternating hemispheres. Thus, VP ionotropic glutamate receptors are critical mediators of the expression of place preference and motor adaptations subsequent to repeated morphine exposure.
评估了腹侧苍白球（VP）内离子型谷氨酸受体在条件性位置偏爱（CPP）表达以及对吗啡的运动适应性方面的作用。给经VP插管的大鼠进行为期3天的条件训练，上午将生理盐水与一个不同的腔室配对，下午将吗啡（8mg/kg腹腔注射或其溶剂）与另一个腔室配对。这导致：（a）1天后在无药物的大鼠中出现CPP表达，而预先经VP内注射谷氨酸拮抗剂混合物（DL-2-氨基-5-磷酸戊酸锂盐[AP-5]+6-氰基-7-硝基喹喔啉-2,3-二酮二钠盐[CNQX]）可阻断该表达；（b）18天后急性吗啡激发后出现运动功能变化，而如果在激发前10天每天在交替的半球单侧注射谷氨酸拮抗剂，则不会出现这种运动功能变化。因此，VP离子型谷氨酸受体是反复接触吗啡后位置偏爱表达和运动适应性的关键介质。
