ARCHITECTURE AND CELL STRUCTURES IN DISTAL NEPHRON OF RAT-KIDNEY

  • 1 January 1978
    • journal article
    • research article
    • Vol. 17  (1) , 197-211
Abstract
Using semi-thin sections of marked tubules of the rat kidney, the distal part of the nephron was represented in toto for the 1st time and reconstructed in its course from the thick part of Henle''s loop to its junction with another collecting tubule. The shape of the model accords well with observations in vivo. Light microscopy and EM were used; four types of cells were differentiated: type 1 (Mittelstueck) cell; type 2 (intermediate) cell; type 3 (light) cell and type 4 (intercalated) cell. Pars recta and pars convoluta of the distal nephron consisted of type 1 (Mittelstueck) cells; pars arcuata and pars recta of the cortical collecting duct exhibited type 3 (light) and type 4 (intercalated) cells; in the connecting portion of the distal tubule all 4 types were represented; type 2 (intermediate) and type 4 (intercalated) were the most frequent. The demarcation of the connecting portion according to this definition pointed to a dynamic relationship of the cell structures of the distal nephron, which gained clarity when conditions were experimentally varied. The existence of the connecting portion was affirmed; a cytological characterization of it was given and a definition was recommended.