Moroz L L, Gillette R
Department of Molecular and Integrative Physiology, University of Illinois, Urbana 61801, USA.
J Comp Neurol. 1996 Apr 15;367(4):607-22. doi: 10.1002/(SICI)1096-9861(19960415)367:4<607::AID-CNE10>3.0.CO;2-E.
The distribution of putative nitric oxide synthase (NOS)-containing cells in the opisthobranch mollusc Pleurobranchaea californica was studied histochemically via NADPH-diaphorase (NADPH-d) reduction of Nitro Blue Tetrazolium (NTB). Whole mounts and cryostat sections were prepared from the central nervous system and peripheral organs, including the buccal muscles, esophagus, salivary glands, foot, mantle, and gills. NADPH-d-positive neurons were localized predominantly to the buccal and pedal ganglia as well as to distinct areas of the cerebropleural and visceral ganglia. A variety of identified neurons were positive for NADPH-diaphorase in various central ganglia, including the metacerebral cells of the cerebropleural ganglion, putative locomotor neurons of the pedal ganglia, and buccal motoneurons. Specific staining was observed only in somata of central neurons, whereas neuropil areas remained unstained. However, NADPH-d-reactive axons were dense in buccal ganglion nerves, whereas peripheral nerves and connectives of other ganglia had few or no NADPH-d positive terminals. In the periphery, NADPH-d activity was detected only in a few neurons of the rhinophore and tentacle ganglia. NADPH-d staining was marked in the salivary glands and gills, but there was no or very little staining in the esophagus, buccal mass, and foot. Histochemical stain production required the presence of both beta-NADPH and NBT; alpha-NADPH could not substitute for beta-NADPH. The inhibitor of NOS, 2,6-dichlorophenol-indophenol, at 10(-3) M, totally abolished NADPH-d-positive staining. The apparent high activity of central NADPH-d contrasts with much lower activity in the ganglia of the related gastropod Tritonia. These data suggest a role for nitric oxide as a signal molecule in the central nervous system of Pleurobranchaea.
通过用硝基蓝四氮唑（NTB）进行NADPH - 黄递酶（NADPH - d）还原反应，对后鳃亚纲软体动物加州侧鳃（Pleurobranchaea californica）中假定含一氧化氮合酶（NOS）的细胞进行了组织化学研究。从包括口部肌肉、食管、唾液腺、足部、外套膜和鳃在内的中枢神经系统和外周器官制备了整装标本和冰冻切片。NADPH - d阳性神经元主要定位于口部和足部神经节以及脑胸膜和内脏神经节的不同区域。在各种中枢神经节中，多种已识别的神经元对NADPH - 黄递酶呈阳性，包括脑胸膜神经节的中脑神经元、足部神经节的假定运动神经元和口部运动神经元。仅在中枢神经元的胞体中观察到特异性染色，而神经纤维网区域未染色。然而，NADPH - d反应性轴突在口部神经节神经中密集，而其他神经节的外周神经和连接组织几乎没有或没有NADPH - d阳性终末。在外周，仅在嗅角和触手神经节的少数神经元中检测到NADPH - d活性。唾液腺和鳃中NADPH - d染色明显，但食管、口部团块和足部中没有或几乎没有染色。组织化学染色反应需要同时存在β - NADPH和NBT；α - NADPH不能替代β - NADPH。10⁻³ M的NOS抑制剂2,6 - 二氯酚靛酚完全消除了NADPH - d阳性染色。中枢NADPH - d的明显高活性与相关腹足动物三趾树螺（Tritonia）神经节中低得多的活性形成对比。这些数据表明一氧化氮在加州侧鳃的中枢神经系统中作为信号分子发挥作用。
