Moron Sandro Estevan, Oba Eliane Tie, De Andrade Cássio Arilson, Fernandes Marisa Narciso
Departamento de Cieências Fisiológicas, Universidade Federal de São Carlos, Caixa Postal 676, 13565-905 São Carlos, SP, Brazil.
J Exp Zool A Comp Exp Biol. 2003 Aug 1;298(2):93-104. doi: 10.1002/jez.a.10259.
Chloride cell (CC) responses to ion challenge and plasma ion concentration were evaluated in two ecologically distinct erythrinids, Hoplias malabaricus, an exclusively water-breathing species, and Hoplerythrinus unitaeniatus, a facultative air-breathing fish, at one, two, seven, and 15 days of exposure to deionized water and to ion-rich water. H. malabaricus displayed high CC proliferation on filament and lamellar epithelium during exposure to deionized water and significant CC proliferation in the filament epithelium on the first day of exposure to water rich in NaCl and Ca2+ and in the lamellar epithelium on the first, second, and seventh day of exposure to such water. CC proliferation in H. unitaeniatus occurred only in the lamellar epithelium of fish exposed to deionized water. CC proliferation on both species was not accompanied by significant increase of CC density in contact with the external medium. The increase in the CC fractional area (CCFA) resulted from the increase of individual CC apical surface area on the first and second days of exposure to deionized water in H. malabaricus and only on the first day in H. unitaeniatus. Plasma ions in both erythrinid species showed transitory changes and, on the fifteenth day of exposure to the two types of experimental water, the plasma ion concentration was similar to the control fish. The CC responses of these erythrinid fish showed that CC proliferation depends on previous CC density in the gill and is not related solely to exposure to ion-poor water. Furthermore, CC proliferation in gill epithelium did not always involve an increase of CC density in contact with the external medium.
在暴露于去离子水和富离子水1天、2天、7天和15天的情况下，对两种生态特性不同的红鳍鱼科鱼类——完全靠水呼吸的马拉巴锯脂鲤（Hoplias malabaricus）和兼性空气呼吸的单带红鳍鱼（Hoplerythrinus unitaeniatus）——的氯化物细胞（CC）对离子刺激和血浆离子浓度的反应进行了评估。马拉巴锯脂鲤在暴露于去离子水期间，其鳃丝和鳃小片上皮出现了高度的CC增殖，在暴露于富含NaCl和Ca2+的水的第一天，鳃丝上皮出现了显著的CC增殖，在暴露于此类水的第一天、第二天和第七天，鳃小片上皮出现了显著的CC增殖。单带红鳍鱼的CC增殖仅发生在暴露于去离子水的鱼的鳃小片上皮。两种鱼类的CC增殖均未伴随着与外部介质接触的CC密度的显著增加。CC分数面积（CCFA）的增加是由于马拉巴锯脂鲤在暴露于去离子水的第一天和第二天以及单带红鳍鱼仅在第一天时单个CC顶端表面积的增加。两种红鳍鱼科鱼类的血浆离子均出现了短暂变化，并且在暴露于两种实验水的第15天，血浆离子浓度与对照鱼相似。这些红鳍鱼科鱼类的CC反应表明，CC增殖取决于鳃中先前的CC密度，并非仅与暴露于贫离子水有关。此外，鳃上皮中的CC增殖并不总是涉及与外部介质接触的CC密度的增加。
