[Histological and histochemical studies of the kidney of stickleback Gasterosteus aculeatus L. I. Morphological changes of the kidney epithelial cells during the spawning period].

1; The tubule of kidney of Gasterosteus aculeatus L. consists of four histologically different regions: Proximal tubule I and III, connection segment and collecting tubule. 2. All of tubule segments inclusively the urinary duct out of the proximal tubule I are showing synthesis of secretion. 3. There are producing two various secretion in two distinct species of cells. From the cells of proximal tubule II are secreted and extruded a granular secretion and from the cells of abducted urinary ducts (connection segment, collecting duct and urinary duct) a hyalo-mucous secretion. 4. During the breeding season the morphological variationes were divided into three stadiums, the stadium of differentiation, of producing of secretion and of reproduction. In second stadium were differenced three phases, in particular characterizing by rhythmical variationes of nucleus structure and synthesis of secretion as extrustion. 5. There are discussing the parallels to synthesis of secretion in glandular cells.