Effects of rhomotoxin on cat papillary muscle

Abstract

Clinical experience has demonstrated that rhomotoxin, isolated from the fruits of Rhododendron molle G. Don, has antihypertensive and antiarrhythmic effects. In the present work, its direct actions on cat papillary muscle were as follows:

1.	Rhomotoxin 2.7 μM increased contractility and automaticity induced by adrenaline, but exerted no influence on excitability and functional refractory period.
2.	Rhomotoxin 27.1 μM shortened functional refractory period, decreased excitability and contractility accompanied by the appearance of spontaneous automaticity.

It is suggested that the above effects of rhomotoxin might be due to the change in resting potential of the myocardial cell as a result of altered transmembrane sodium movement.

Keywords

rhomotoxin / cat papillary muscle

References

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