ISSN:
0021-9541
Keywords:
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
In the absence of external HCO3, resting membrane potentials (Vm) in extensor digitorum longus muscle were depolarized as compared to the normal Vm in the presence of HCO3. Removal of Na or Cl from the HCO3-free media induced repolarization. In muscle in HCO3 buffer at 20°C, internal K, Na, and Cl activities were analyzed with liquid ion selective microelectrodes. The averages were respectively, 119.7 ± 2.1, 6.69 ± 0.3, and 3.41 ± 0.06 mM. In a high proportion of cells analyzed, the equilibrium potential for Cl was negative to Vm. Removing external HCO3, decreased internal K while internal Na and Cl increased. An increase in temperature and the application of HCO3 significantly lowered internal activities of both Na and Cl. Removal of HCO3 with temperature held constant caused a rapid depolarization, an increase in internal Na and Cl, and a decrease in internal K. Furosemide (10 μM) induced a repolarization of cells that were previously depolarized in the HCO3-free state, but the drug does not decrease internal Na.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcp.1041250115
