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USGS · 1014556

Effects of prolacton chloride cells opercular membrane of seawater-adapted tilapia

T.M. Herndon·S. D. McCormick·H. A. Bern
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Abstract

Effects of prolactin on morphology and numbers of chloride cells in the opercular membrane of seawater-adapted tilapia ( Oreochromis mossambicus ) have been examined. Following five daily injections of ovine prolactin at a dose of 10 μg · g body wt −1 , blood samples were taken and opercular membranes were removed and stained with a fluorescent mitochondrial dye (dimethylaminostyrylethylpyridiniumiodine), a fluorescent derivative of ouabain (anthroylouabain), and a histological stain specific for the extensive tubular system of chloride cells (zinc-osmium-iodine). Mean plasma osmolarity and sodium increased 23–24% following prolactin injection. An increase in the relative frequency of chloride cells between 20 and 180 μm 2 in cross-sectional area and a decrease in the relative frequency of chloride cells greater than 180 μm 2 were observed following prolactin injections. Average cell size decreased 46–70% and cell height decreased 26–38% following prolactin injections. There was no significant change in cell density. Anthroylouabain staining was observed in both prolactin- and saline-injected fish, and no significant effect on Na + ,K + -adenosinetri-phosphatase activity was seen in either opercular membrane or gill tissue. The results demonstrate an effect of prolactin on chloride cell size and provide a morphological correlate for decreased secretory activity of chloride cells following prolactin injections.

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T.M. Herndon, S. D. McCormick, H. A. Bern. 1991. Effects of prolacton chloride cells opercular membrane of seawater-adapted tilapia. https://doi.org/10.1016/0016-6480(91)90032-2

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