革胡子鲇触须和口腔粘膜的味觉器官

TASTE ORGANS IN THE MOUTH AND BARBEL OF CLARIAS LEATHER

应用组织学切片和电镜扫描的方法，对革胡子鲇上颌须和口腔味蕾的组织形态特征进行了比较研究．发现分属于两个亚感觉通路（迷走叶和面叶味觉系统）的两类味蕾，其感受器细胞组成和形态结构没有明显的不同，主要区别为味蕾是否通过味孔与外界接触，以及在上皮中的分布状况．革胡子鲇口腔内也有少量面神经叶支配的味蕾位于口腔横瓣上．由迷走神经叶支配的味蕾成簇集中腭部．感觉细胞的微绒毛突出于顶端，有味刺激物能直接到达味感觉细胞膜上．其形态结构表明，鱼类味觉是接触性或近距离化学感受器．

The taste buds in the oral cavity and maxillary barbel of Clarias leather are observed by the histological techniques and scanning electron microscopeSEM). When comparative methods are used to investigate the morphological characteristics of the two kinds of taste buds, We found that there are no obvious differences of histomor-phological construction of the taste cells between them although these taste buds are made up of two submodalities(facial and vagal taste systems). The main difference lies in where and how they are located in epithlia and whether they have the taste pores. The receptor of the facial taste system is also distributed in the transverse valvevalvula oralis ) in the fish′s mouth,but there are more in the barbel.The receptor of the vagal taste system is concentrated in the palatum.The taste buds lie at the apex of a small pepilla. The typical cells of this taste bud have sensory villi extending from their apical process into a thin mucous layer.So a food stimulus can directly reach the membrane of taste cells.It is in still line with the suggestion that fish gustation functions primarily as a contact sense.