ISSN:
1432-2013
Keywords:
pH
;
uterus
;
calcium current
;
potassium current
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Spontaneous contraction of uterine smooth muscle is enhanced by alkalinization and depressed by acidification. We have investigated the ionic currents responsible for this in single myometrial cells. Intracellular acidification (20 mM butyrate) at constant external pH depressed the magnitude of the calcium current to 58±6% of control, but had little effect on outward currents. Similar but slower effects were also observed when the extracellular pH was lowered to 6.9 (56±9% of control). Correspondingly, when the intracellular or extracelluar pH was elevated (20 mM NH4Cl or pH 7.9 respectively) the calcium current magnitude increased (165±15 % in NH4Cl; 136±2 % at pH 7.9) and there was, again, no effect on the outward currents. These observations are consistent with the effects of pH on spontaneous contractile activity being due to an effect on the membrane calcium current.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00374388
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