大鼠旁巨细胞外侧核自发放电神经元的类型和分布

为进一步探讨大鼠旁巨细胞外侧核（ＰＧＣＬ）在呼吸调控中的作用，采用细胞外记录法，探查了在麻醉、自主呼吸下的１４只ＳＤ大鼠的ＰＧＣＬ尾半侧（ｃＰＧＣＬ）神经元的自发放电类型，分析了呼吸相关神经元（ＲＲＮｓ）的放电样式和分布。结果：在ｃＰＧＣＬ区共记录到２３７个自发放电神经元，其中ＲＲＮｓ３９个，非呼吸相关神经元（ＮＲＲＮｓ）１９８个。ＮＲＲＮｓ主要呈紧张性放电样式（ｎ＝１７８）。ＲＲＮｓ中，吸气神经元（ＩＮｓ）、呼气神经元（ＥＮｓ）、跨时相神经元（ＰＳＮｓ）各为２４、１２和３个。ＩＮｓ的放电样式为递增型（２０／２４个）、稳定型或钟型（４／２４个）；ＥＮｓ为递减型（７／１２个）、稳定型或钟型（５／１２个）；ＰＳＮｓ有吸气－呼气（ＩＥＮｓ，２／３个）和呼气－吸气（ＥＩＮｓ，１／３个）跨时相神经元，均为稳定型或钟型放电样式。ＲＲＮｓ主要分布在ｃＰＧＣＬ背外侧份，越近尾端越密集。上述结果提示ＰＧＣＬ是呼吸调控的重要中枢部位之一

Patterns and Distribution of the Spontaneously Discharges Neurons in the Nucleus Paragigantocellularis Lateralis of Rats

Using extracellular recording technique, we systematically explored the spontaneously discharging neruons in the caudal half of nucleus paragigantocellularis lateralis (cPGCL) in anesthetized and spontaneously breathing Sprague Dawley rats. The discharge patterns of the neurons and the distribution of the respiratory related neurons (RRNs) in this PGCL area were analysed. A total of 237 neurons with spontaneous discharge were stably recorded in 14 rats. Among them 39 were RRNs and 198 non RRNs (NRRNs). The discharge patterns of the 198 NRRNs were primarily tonic ( n =178). Of the 39 RRNs, 24 were inspiratory (INs), 12, expiratory (ENs), and 3, phase spanning (PSNs). The INs could be further classified into augmenting ( n =20) and constant or bellshaped ( n =4) INs, and the ENs, into decrementing ( n =7) and constant or bell shaped ( n =5) ENs. The phase spanning neurons showed a constant or bell shaped pattern of discharge, including inspiratory exspiratory (IENs, n =2) and expiratory inspiratory (EIN, n =1) phase spanning ones. Most of the RRNs were distributed in the dorsolateral portion of the cPGCL area and tended to concentrate in the more caudal part. These results suggest that PGCL is one of the important neural substrates responsible for the regulation of rhythimic respiration.