ISSN 0869-6632 (Print)
ISSN 2542-1905 (Online)

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Klimova O. A., Semenova M. A., Anishchenko T. G., Igosheva N. B. Normalized entropy in the evaluation of cardiovascular responses to different perturbations in male and female rats. Izvestiya VUZ. Applied Nonlinear Dynamics, 2003, vol. 11, iss. 2, pp. 108-115. DOI: 10.18500/0869-6632-2003-11-2-108-115

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Normalized entropy in the evaluation of cardiovascular responses to different perturbations in male and female rats

Klimova Oksana Anatolevna, Saratov State University
Semenova Maria Alekseevna, Saratov State University
Anishchenko Tatyana Grigorievna, Saratov State University
Igosheva Natalia Borisovna, Cambridge Clinical Trials Unit

In this research we studied the cardiovascular sensitivity to parasympathetic blockade in normal and castrated male and female rats under usual and stress conditions using the traditional physiological measures and a new measure of complexity of blood pressure dynamics - normalized entropy Е/Н. The results showed that changes in E/H were more pronounced and prolonged in comparison with heart rate and blood pressure. Also, unlike the latter, Е/Н increased in one part оf rats аn decreased in another part оf ones. These quantitative аnd qualitative particularities in Е/Н changes give evidence that using a new measure of complexity degree of blood pressure signal one can receive an additional information about the changes in cardiovascular system evoked by different perturbations.

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The research was partially supported by CRDF(REC-006) grant and Russian Ministry of Education grant RD 02-1.4-261.
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