SINGLE NEURONAL ACTIVATION BY MULTIPLE OPIATE SUBSTRATES

本建议的长期目标是帮助澄清 阿片类镇痛药如何缓解疼痛的问题。 有几个位点， 大脑中阿片受体的位置和电和/或 化学（鸦片）激活产生镇痛作用。 这些结构连接 沿着多条路线到达疼痛通路。 全身注射鸦片制剂 必须以复杂的动态方式激活许多这些底物。 的 提出的方法是检查单一和联合激活的影响 大鼠中脑导水管周围灰质（PAG） 和旁巨细胞网状核（PGC）， 中缝大核（NRM）和三叉神经元的单个神经元反应 尾侧核（TNC）。 将Met-脑啡肽微插管至PAG中 和PGC单独和一起，将确定是否（和 如果是这样，这两种阿片底物如何影响NRM中的同一细胞， 在TNC中，是疼痛通路的起源。 还将进行吗啡在PGC中作用的剂量反应研究。 时间允许，PGC病变对PAG吗啡诱发的修饰的影响 NRM和TNC单位的活动也将被调查。

The long term objective of the present proposal is to help clarify the question of how opiate analgesics relieve pain. There are several loci in brain where opiate receptors are located and where electrical and/or chemical (opiate) activation produces analgesia. These structures connect to pain pathways along multiple routes. A systemic injection of opiates must activate many of these substrates in a complex dynamic manner. The approach proposed is to examine effects of single and conjoint activation of two opiate substrates in rat, the midbrain periacqueductal gray (PAG) and the nucleus reticularis paragigantocellularis (PGC), on recorded responses of single neurons in nucleus raphe magnus (NRM) and in trigeminal nucleus caudalis (TNC). Met-Enkephalin will be microcannulated into PAG and PGC singly and together and it will be determined whether or not (and if so, how) these two opiate substrates can influence the same cell in NRM, an opiate substrate itself; and in TNC, the origin of a pain pathway. Dose-response studies of the effects of morphine in PGC will also be done. Time permitting, effects of PGC lesions on PAG morphine-evoked modification of NRM and TNC unit activity will also be investigated.