Effects of Calcium Antagonists and Other Metabolic Modulators on in Vitro Calcium Deposition on Otoliths in the Rainbow Trout Oncorhynchus mykiss.
Effects of Calcium Antagonists and Other Metabolic Modulators on in Vitro Calcium Deposition on Otoliths in the Rainbow Trout Oncorhynchus mykiss.
复制标题
钙拮抗剂和其他代谢调节剂对虹鳟鱼耳石体外钙沉积的影响。
DOI：
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发表时间：
1995
期刊：
影响因子：
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通讯作者：
Masanori Yoshida
中科院分区：
文献类型：
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作者：
Y. Mugiya;Masanori Yoshida
使用虹鳟鱼含耳石球囊的分离制备物，药理学地检查了血钙向耳石穿过球囊上皮的转运。添加到孵育培养基中的甘露醇几乎没有渗透到内淋巴中，表明细胞间连接紧密，钙通过细胞旁途径扩散。在培养液中加入羊毛脂或钆可使耳石钙沉积速率显著降低。维拉帕米和地尔硫卓对沉积没有影响，而活性蓝使沉积率降低至对照的60%。虽然在孵育液中用胆碱替代钠并没有改变耳石上钙沉积的速率，但哇巴因以浓度依赖性方式降低了该速率。氯丙嗪也能有效地降低。这些结果表明，受体操纵的钙通道促进钙流入囊状细胞的基底外侧膜和胞质钙被挤出到耳石的Na+ Ca2+交换器和ATP依赖性钙泵的远端膜。
Translocation of blood calcium to otoliths across the saccular epithelium was examined pharmaco logically using an isolated preparation of the otolith-containing sacculus from rainbow trout. Mannitol added to the incubation medium virtually did not permeate into endolymph, indicating that intercellu lar junctions are tight for calcium to diffuse through a paracellular pathway. The addition of lantha num or gadolinium to the incubation medium led to a marked decrease in the rate of calcium deposition on otoliths. Verapamil and diltiazem had no effect on the deposition, while Reactive blue reduced the rate to 60% of the control. Although the replacement of sodium with choline in the incubation medium did not change the rate of calcium deposition on otoliths, ouabain reduced the rate in a concentration dependent way. Chlorpromazine was also effective for the reduction. These results suggest that receptor-operated calcium channels facilitate calcium influx into saccular cells across the basolateral membrane and that cytosolic calcium is extruded to the otolith across the distal membrane by the Na+ Ca2+ exchanger and ATP-dependent calcium pump.