Sensory neuroanatomy of a skin‐penetrating nematode parasite Strongyloides stercoralis. II. labial and cephalic neurons
Sensory neuroanatomy of a skin‐penetrating nematode parasite Strongyloides stercoralis. II. labial and cephalic neurons
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皮肤穿透线虫寄生虫粪类圆线虫的感觉神经解剖学。
DOI：
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
G. Schad
中科院分区：
文献类型：
--
作者：
A. E. Fine;F. Ashton;V. Bhopale;G. Schad
粪类圆线虫感染性幼虫的宿主识别、接触和皮肤穿透是介导从自由生活到寄生生活过渡的至关重要的行为功能。虫体前端的感器可能在这些过程中起重要作用。除了主要的化学感受器，端头类，这是中心的重要性，幼虫有16个推定的机械感器。有六个内唇感器：两个背侧，两个腹侧和两个侧。两个背侧和腹侧对各由两个神经元支配，而每个侧感器是单独支配的。6个外唇感器和4个头感器均为单神经支配。所有这些都具有机械感受器的特征：它们与外部环境紧密相关，并与上覆的角质层密切相关。在远端，它们的树突状突起含有颗粒物质和相关的微管。除了两个例外，相关的神经元细胞体位于神经环附近的外侧神经节中，它们的位置与自由生活的线虫（秀丽隐杆线虫）中的同源物非常相似。然而，两个神经元对的细胞体，两个背侧内唇神经元和两个腹侧内唇神经元每侧之一，被发现远远领先于其余的细胞体。所有的唇和头感受器显然是机械感受器，补充了发育良好的化学感受器。据推测，感染性幼虫需要触摸和拉伸感受器，不仅通过寻找不规则的进入点来启动皮肤渗透，而且还穿透组织到达最终的肠道目的地。神经学比较杂志389：212-223，1997.© 1997 Wiley利斯公司
Host recognition, contact, and skin‐penetration by Strongyloides stercoralis infective larvae are crucially important behavioral functions mediating transition from free‐living to parasitic life. The sensilla of the worm's anterior tip presumably play an important role in these processes. Besides the main chemosensilla, the amphids, which are of central importance, the larva has 16 putative mechanosensilla. There are six inner labial sensilla: two dorsal, two ventral, and two lateral. The two dorsal and ventral pairs are each innervated by two neurons, whereas each lateral sensillum is singly innervated. The six outer labial and four cephalic sensilla are all singly innervated. All of these have the characteristics of mechanoreceptors: they are closed to the external environment, and closely associated with the overlying cuticle. Distally, their dendritic processes contain granular material and associated microtubules. With two exceptions, the relevant neuronal cell bodies lie in lateral ganglia adjacent to the nerve ring, their positions remarkably similar to those of their homologues in the free‐living nematode, Caenorhabditis elegans. Cell bodies of two neuronal pairs, one of two dorsal inner labial neurons and one of two ventral inner labial neurons per side, are however, found far anterior to the remaining cell bodies. All labial and cephalic sensilla are apparently mechanoreceptors, complementing the well‐developed chemosensilla. Presumably infective larvae require touch and stretch receptors, not only to initiate skin penetration by finding irregularities as points of access, but also to bore through tissue to reach their ultimate enteral destination. J. Comp. Neurol. 389:212–223, 1997. © 1997 Wiley‐Liss, Inc.
DOI：
10.1073/pnas.90.6.2227
发表时间：
1993-03-15
影响因子：
11.1
作者：
KAPLAN, JM;HORVITZ, HR
通讯作者：
HORVITZ, HR