In:
The Journal of General Physiology, Rockefeller University Press, Vol. 43, No. 3 ( 1960-01-01), p. 555-571
Abstract:
Segments of the colon of anesthetized rats have been perfused in vivo with isotonic NaCl solutions and isotonic mixtures of NaCl and mannitol. Unidirectional and net fluxes of Na and Cl and the net fluxes of water and mannitol have been measured. Net water transport was found to depend directly on the rate of net Na transport. There was no water absorption from these isotonic solutions in the absence of net solute transport, indicating that water transport in the colon is entirely a passive process. At all NaCl concentrations studied, the lumen was found to be electrically negative to the surface of the colon by 5 to 15 mv. Na fluxes both into and out of the lumen were linear functions of NaCl concentration in the lumen. Net Na absorption from lumen to plasma has been observed to take place against an electrochemical potential gradient indicating that Na is actively transported. This active Na transport has been interpreted in terms of a carrier model system. Cl transport has been found to be due almost entirely to passive diffusion.
Type of Medium:
Online Resource
ISSN:
1540-7748
,
0022-1295
DOI:
10.1085/jgp.43.3.555
Language:
English
Publisher:
Rockefeller University Press
Publication Date:
1960
detail.hit.zdb_id:
1477246-2
SSG:
12
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