Ethridge L, Benjamin M
Cell Tissue Res. 1977 Aug 26;182(3):371-82. doi: 10.1007/BF00219772.
The time sequence of the ultrastructural changes in the prolactin cells of the adult guppy, Poecilia reticulata, was studied in freshwater fish transferred to 1/3 seawater for 1, 4, 11 and 28 days. The morphological changes were slight and only detectable by quantitative (morphometric) procedures. The secretory granules showed a "biphasic' response to the altered environmental salinity, but the volume density of the Golgi apparatus progressively declined throughout the experiment. After an initial decrease in the volume density of the RER, that organelle regained its original prominence by 11 days in 1/3 seawater. The volume density of the nucleus was markedly higher in fish 28 days after transfer to 1/3 seawater than in any other group. Cell volume estimations showed that a shrinking of the cytoplasm rather than a swelling of the nucleus accounted for the high volume density figure. The changes in the volume density of the mitochondria closely paralleled those of the RER. Profiles of exocytosed granules were rarely found in any of the groups, but were least frequent in fish kept in 1/3 seawater for 28 days, when dense (lysosomal?) bodies were most abundant. The quantitative methods high-lighted some discrepancies in the rate and magnitude of the changes shown by some organelles and have led the authors to suggest that during adaptation of fish to dilute seawater, synthesis and release may not be coupled processes in the prolactin cell of P. reticulata.
在成年孔雀鱼（Poecilia reticulata）的催乳素细胞超微结构变化的时间序列研究中，将淡水鱼转移到1/3海水环境中1、4、11和28天。形态学变化轻微，只有通过定量（形态测量）程序才能检测到。分泌颗粒对环境盐度变化呈现“双相”反应，但在整个实验过程中，高尔基体的体积密度逐渐下降。粗面内质网（RER）的体积密度最初下降后，在1/3海水中11天时该细胞器恢复到原来的突出程度。转移到1/3海水28天后的鱼的细胞核体积密度明显高于其他任何组。细胞体积估计表明，细胞质收缩而非细胞核肿胀导致了高体积密度数值。线粒体体积密度的变化与粗面内质网的变化密切平行。在任何一组中很少发现胞吐颗粒的轮廓，但在1/3海水中饲养28天的鱼中最为少见，此时致密（溶酶体样？）体最为丰富。定量方法突出了一些细胞器所显示的变化速率和幅度的差异，并使作者认为，在鱼类适应稀释海水的过程中，网纹孔雀鱼催乳素细胞中的合成和释放可能不是耦合过程。
