Beschreibung:
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<jats:list-item><jats:p>Heptaminol stopped or delayed the progressive decline in tension which characterizes the phenomenon of fatigue in frog isolated twitch muscle fibre.</jats:p></jats:list-item>
<jats:list-item><jats:p>Heptaminol had no action on the sodium, potassium and calcium voltage‐dependent ionic conductances.</jats:p></jats:list-item>
<jats:list-item><jats:p>The hypothesis of an action via an internal alkalinization was tested by comparison with the action of NH<jats:sub>4</jats:sub>Cl. Both substances increased the tension.</jats:p></jats:list-item>
<jats:list-item><jats:p>The action of heptaminol was suppressed in sodium‐free (TRIS) solution or in the presence of amiloride while the action of NH<jats:sub>4</jats:sub>Cl was always observed.</jats:p></jats:list-item>
<jats:list-item><jats:p>These results could be explained by a stimulation of the Na/H antiport by heptaminol.</jats:p></jats:list-item>
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