HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Bennett, M. R. Search for Related Content PubMed PubMed Citation Articles by Bennett, M. R.

1. A study has been made of the effects of Na⁺ and Ca²⁺ on the responses generated by intracellular current pulses in smooth muscle cells of the guinea-pig vas deferens and upon the propagated action potential.

2. Reduction of the extracellular Na⁺ activity (a_Na) to less than 30 mM did not alter the characteristics of the spike-like response to intracellular current pulses (the active response) or of the propagated action potential.

3. Reduction of the extracellular Ca²⁺ activity (a_Ca) to 0·1 mM decreased the resting input resistance of the cells but increased the input resistance during the crest of the active response. Reduction of Ca²⁺ decreased the overshoot of the action potential by 22 mV per tenfold change in Ca²⁺ and the resting potential by 25 mV per tenfold change.

4. Reduction of the extracellular Ca²⁺, keeping the product a_Ca/a²_Na constant, did not change the resting potential, but decreased the action potential overshoot by 20 mV per tenfold change.

5. It is suggested that part of the current responsible for the rising phase of the action potential is carried by Ca²⁺.