Wang X Y, Wong W C, Ling E A
Department of Anatomy, National University of Singapore, Singapore.
J Auton Nerv Syst. 1996 Apr 20;58(1-2):51-5. doi: 10.1016/0165-1838(95)00119-0.
The distribution of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d), a marker for nitric oxide synthase (NOS), in the nerves of gastrointestinal sphincters in guinea pigs was investigated to throw some light on the role of nitric oxide (NO) in these sphincteric regions. The nerve fibres with NADPH-d activity were observed chiefly in the circular muscle layer of the wall of gastrointestinal sphincters. Compared with the adjacent non-sphincteric regions, the proportions of NADPH-d positive myenteric neurons in the lower esophageal sphincter (LES), pyloric sphincter (PS) and internal anal sphincter (IAS) were higher (P < 0.05). The densities of NADPH-d-positive fibres in the circular muscle of above sphincteric regions were also higher (in LES P < 0.01; in PS and IAS P < 0.05). Within the circular muscle of LES, some discrete NADPH-d-positive intrinsic nerve cell bodies, usually smaller than their outlying myenteric neurons, were also observed. The dense distribution of NADPH-d-positive fibres within the circular muscles of gastrointestinal sphincteric regions suggests that NO, as a non-adrenergic non-cholinergic (NANC) inhibitory neurotransmitter, might play an important role in the neuronal regulation of the guinea-pig gastrointestinal sphincters.
为了深入了解一氧化氮（NO）在豚鼠胃肠道括约肌区域的作用，研究了烟酰胺腺嘌呤二核苷酸磷酸 - 黄递酶（NADPH - d，一氧化氮合酶（NOS）的标志物）在豚鼠胃肠道括约肌神经中的分布。具有NADPH - d活性的神经纤维主要见于胃肠道括约肌壁的环形肌层。与相邻的非括约肌区域相比，食管下括约肌（LES）、幽门括约肌（PS）和肛门内括约肌（IAS）中NADPH - d阳性肌间神经元的比例更高（P < 0.05）。上述括约肌区域环形肌中NADPH - d阳性纤维的密度也更高（LES中P < 0.01；PS和IAS中P < 0.05）。在LES的环形肌内，还观察到一些离散的NADPH - d阳性固有神经细胞体，其通常比周围的肌间神经元小。胃肠道括约肌区域环形肌内NADPH - d阳性纤维的密集分布表明，NO作为一种非肾上腺素能非胆碱能（NANC）抑制性神经递质，可能在豚鼠胃肠道括约肌的神经调节中起重要作用。
