Morpho-functional study of nitric oxide synthase-positive neurons in the brain stem that are involved in oral sensori-motor function.

表达神经元型一氧化氮合酶(NNOS)或烟酰胺腺嘌呤二核苷酸磷酸黄递酶(NADPH-d)的神经元被认为按需产生一氧化氮(NO)。用神经损伤法和WGA-HRP标记的口内及口周传入中枢终末野用组织化学方法研究NADPH-d的活性和空间分布。在尾侧亚核(SpVc)，多数标记神经元位于浅层，少数位于大细胞区。SpVo/Sn区和背内侧SpVc的NADPH-d阳性神经元主要与舌神经的跨神经节标记终末区重叠，部分与下牙槽神经、精神神经和鼓索神经的终末区重叠。切断舌神经后，双侧SpVo/Sn区NADPH-d阳性神经元的数量显著减少。舌神经和/或牙髓的炎性侮辱显著增加…SpVo/Sn区和SpVc区NADPH-d阳性神经元数目较多。因此，SpVo/Sn区和SpVc区的NADPH-d阳性神经元可以接受来自口内结构，尤其是来自舌的初级传入信息，并受其调节。神经切断后原代神经元表达的nNOS活性参与神经再生。由于全身应用L-硝基精氨酸甲酯(L-NAME；一氧化氮合酶阻断剂)减少了下牙槽神经进入牙髓的数量。将完全弗氏佐剂(CFA)注入后足垫可引起长时间的痛觉过敏，持续时间超过一周。注射CFA后3d，L4-5背角NADPH-d或NOS阳性神经元数量增加。给予L-NAME减佐剂可引起长时间的热痛敏，但不能引起正常痛觉和急性痛敏。因此，脊髓背角中NO的增加可能参与痛觉过敏的维持和/或病理性伤害性感觉的延长。较少

Neurons that express neuronal nitric oxide synthase (nNOS) or Nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) are considered to produce nitric oxide (NO) on demand. NADPH-d activity and the spatial distribution were characterized histochemically with nerve insults and the WGA-HRP-labeled central terminal fields from the intra- and peri-oral afferents. In the subnucleus caudalis (SpVc), most labeled neurons were in the superficial zone, and smaller numbers were in the magnocellular zone. The NADPH-d-positive neurons in the SpVo/Sn and the dorsomedial SpVc overlapped mostly with the transganglionically labeled terminal field from the lingual nerve, partly with the terminal field from the inferior alveolar, mental and chorda tympani nerves. A statistically significant reduction in the number of NADPH-d-positive neurons was seen bilaterally in SpVo/Sn when the lingual nerve was transected. Inflammatory insults to the lingual nerve and/or tooth pulps significantly increased … More the number of NADPH-d-positive neurons in SpVo/Sn, and SpVc. Thus NADPH-d-positive neurons in the SpVo/Sn and SpVc could receive and be regulated by primary afferent inputs from intra-oral structures especially from the tongue. Activity of nNOS that expressed in primary neurons after nerve transection is involved in nerve regeneration. Because systemic administration of L-nitro arginine methyl ester (L-NAME; NOS blocker) decreased the number of regenerated inferior alveolar nerve into the tooth pulp. Injection of complete Freund's adjuvant (CFA) into hind foot pad induces prolonged hyperalgesia for more than one week. Three days after injection of CFA the number of NADPH-d or NOS-positive neurons increased in the L4-5 dorsal horn. Administration of L-NAME reduced adjuvant induced prolonged thermal hyperalgesia but not normal nociception and acute hyperalgesia. Thus increased NO in the spinal dorsal horn could be involved in maintenance of hyperalgesia and/or prolonged pathological nociception. Less