Small Dana M, Scott Thomas R
Department of Psychiatry, The John B Pierce Laboratory, Yale University School of Medicine, New Haven, Connecticut 06519, USA.
Ann N Y Acad Sci. 2009 Jul;1170:343-6. doi: 10.1111/j.1749-6632.2009.03918.x.
In rodents there is an important gustatory relay in the pontine parabrachial nucleus (PbN) upon which much centrifugal modulation occurs to guide complex feeding behaviors. From the PbN two separate projections arise, one which synapses in the parvicellular medial tip of the ventroposteromedial nucleus of the thalamus, which in turn sends axons to taste cortex. This pathway is thought to be largely sensory in nature. A second pathway projects widely to the ventral forebrain areas including hypothalamus, and amygdala and is thought to be largely affective in nature. Recent support for this dissociation comes from Hajnal and Norgren who found that lesions of the pons but not the thalamus disrupted dopamine overflow in the accumbens during sucrose licking. Remarkably, the pontine taste relay does not appear to exist in human and nonhuman primates, or if it does exist, its role is much reduced. The aim of this symposium is to outline the role of the PbN in sensory and affective processing of taste in rodents and to speculate upon the implications of interspecies differences for tasting and feeding in primates. The specific aim of the introductory comments will be to provide an overview of evidence for these interspecies differences to set the stage for the remaining papers.
在啮齿动物中，脑桥臂旁核（PbN）存在一个重要的味觉中继站，其上发生大量离心调节以引导复杂的进食行为。从PbN发出两条独立的投射，一条投射到丘脑腹后内侧核的小细胞内侧尖端并与之形成突触，丘脑腹后内侧核进而将轴突发送至味觉皮层。这条通路在本质上被认为主要是感觉性的。第二条通路广泛投射到包括下丘脑和杏仁核在内的腹侧前脑区域，在本质上被认为主要是情感性的。最近， Hajnal和Norgren的研究为这种分离提供了支持，他们发现脑桥损伤而非丘脑损伤会破坏蔗糖舔舐过程中伏隔核内的多巴胺溢出。值得注意的是，脑桥味觉中继站在人类和非人类灵长类动物中似乎并不存在，或者即使存在，其作用也大大降低。本次研讨会的目的是概述PbN在啮齿动物味觉的感觉和情感加工中的作用，并推测种间差异对灵长类动物味觉和进食的影响。引言部分评论的具体目的将是概述这些种间差异的证据，为其余论文奠定基础。
