Smith Gerard P
Department of Psychiatry, Weill Medical College of Cornell University, 21 Bloomingdale Road, White Plains, NY 10605, USA.
Appetite. 2004 Aug;43(1):11-3. doi: 10.1016/j.appet.2004.02.006.
To investigate the hypothesis that central dopamine mediates the rewarding effect of orosensory stimulation by sucrose that increases eating, specific dopamine antagonists were administered prior to sham-feeding tests in which rats ingested various concentrations of sucrose. Sham feeding (SF) was used to preserve the orosensory stimulation of sucrose while it eliminated sucrose's postingestive effects. The antagonists decreased intake as a function of the concentration of sucrose. Microstructural analysis of licking demonstrated that the antagonists did not affect the motor performance of licking. Thus, the inhibitory effect of the antagonists on intake was due to a decrease in the rewarding effect of sucrose. Microdialysis experiments demonstrated that dopamine was released in the nucleus accumbens during SF and that the synaptic action of dopamine in the accumbens was necessary for the normal rewarding effect of orosensory stimulation by sucrose.
为了研究中枢多巴胺介导蔗糖口腔感觉刺激的奖赏效应从而增加进食这一假说，在假饲试验前给予特定的多巴胺拮抗剂，试验中大鼠摄入不同浓度的蔗糖。假饲（SF）用于保留蔗糖的口腔感觉刺激，同时消除蔗糖的摄食后效应。拮抗剂使摄入量随蔗糖浓度的变化而减少。舔舐的微观结构分析表明，拮抗剂并不影响舔舐的运动表现。因此，拮抗剂对摄入量的抑制作用是由于蔗糖奖赏效应的降低。微透析实验表明，在假饲过程中多巴胺在伏隔核释放，且伏隔核中多巴胺的突触作用对于蔗糖口腔感觉刺激的正常奖赏效应是必需的。
