Dataset Information

S- and P-type cobra venom cardiotoxins differ in their action on isolated rat heart.

ABSTRACT:

Background

The cardiovascular system is one of the first systems to be affected by snake toxins; but not many toxins exert a direct effect on the heart. Cobra venom cardiotoxins are among those few toxins that attack the heart. Although the two cardiotoxin types (S and P) differ in their central-loop structure, it is not known whether they differ in their effect on the mammalian heart. We compared the effects of S- and P-type cardiotoxins, CTХ-1 and CTХ-2, respectively, from the cobra Naja oxiana, on the isolated rat heart.

Methods

An isolated rat heart perfused according to the Langendorff technique was used in this study to investigate the activity of cardiotoxins CTX-1 and CTX-2. The following parameters were registered: the left ventricular developed pressure, calculated as the difference between systolic and diastolic pressure in the left ventricle, the end-diastolic pressure, the heart rate, time to maximal end-diastolic pressure (heart contracture), and time to depression of the heart contraction.

Results

Both cardiotoxins at the concentration of 5 μg/mL initially produce a slight increase in systolic intraventricular pressure, followed by its rapid decrease with a simultaneous increase in diastolic intraventricular pressure until reaching contracture. CTX-2 blocks cardiac contractions faster than CTX-1; in its presence the maximum diastolic pressure is reached faster and the magnitude of the developed contracture is higher.

Conclusion

The P-type cardiotoxin CTX-2 more strongly impairs rat heart functional activity than the S-type cardiotoxin CTX-1, as expressed in its faster blockage of cardiac contractions as well as in more rapid development and greater magnitude of contracture in its presence.

SUBMITTER: Averin AS

PROVIDER: S-EPMC8978908 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Publications

S- and P-type cobra venom cardiotoxins differ in their action on isolated rat heart.

Averin Alexey S AS Goltyaev Mikhail V MV Andreeva Tatyana V TV Starkov Vladislav G VG Tsetlin Victor I VI Utkin Yuri N YN

The journal of venomous animals and toxins including tropical diseases 20220404

<h4>Background</h4>The cardiovascular system is one of the first systems to be affected by snake toxins; but not many toxins exert a direct effect on the heart. Cobra venom cardiotoxins are among those few toxins that attack the heart. Although the two cardiotoxin types (S and P) differ in their central-loop structure, it is not known whether they differ in their effect on the mammalian heart. We compared the effects of S- and P-type cardiotoxins, CTХ-1 and CTХ-2, respectively, from the cobra <i ...[more]

PMID: 35432493

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Dataset Information

S- and P-type cobra venom cardiotoxins differ in their action on isolated rat heart.

Background

Methods

Results

Conclusion

Publications

S- and P-type cobra venom cardiotoxins differ in their action on isolated rat heart.

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