Studies of vertebrate kidney. VI. Histochemical localization of phospholipids in kidneys of fishes from different habitats.

Six fish species living in different habitats such as fresh water, estuarine, and marine were studied for the distribution of phospholipids in various regions of the kidney. Well known histochemical methods, including those for choline-containing phospholipids were employed. The distribution pattern of phospholipids in different parts of the kidney such as the brush border, basal border and cytoplasmic granules of the proximal tubule cells, the cytoplasmic granules of the distal tubule cells, glomeruli and interstitial cells is given. Choline-containing phospholipids are present in the brush border of the proximal tubules of all the species studied and in the basal border of some. In the discussion an attempt at correlation of this histochemical pattern with the excretory functions and osmoregulation in these fishes is given.