AJP - Renal Physiology, Vol 241, Issue 3 203-F218, Copyright © 1981 by American Physiological Society
Functional segmentation of the mammalian nephron
H. R. Jacobson
Although each of the major experimental techniques applied to the study of
renal physiology has provided its fair share of new information, the
technique of in vitro microperfusion of nephron segments is notable for two
major contributions. First, it has supplied a more direct and controlled
means of studying epithelial transport processes, some of which already
have helped us to understand certain aspects of kidney function and others
of which have yet to find their application in unraveling the mysteries of
the kidney. Second, in the process of delineating these transport
characteristics, it has served to emphasize the epithelial specialization
present in the kidney, providing functional counterparts to the already
recognized anatomic heterogeneity present in the kidney. In this second
role microperfusion has spawned the application of biochemical analysis of
the hormonal responses of various nephron segments and contributed to the
impetus for work in culturing the various cell types present in each
nephron segment. This review outlines the functional characteristics of the
11 major segments of the nephron, incorporating what has been learned from
some of the biochemical work on hormone response and correlating the latter
with transport events.
