Electrical Activity of the Uterus in Rats at Different Stages of the Estrous Cycle
- Authors: Rutkevich S.A.1,2, Pihul P.G.1, Panimatska Y.D.1, Kazakevich V.B.1,2, Veres I.A.2, Sidorov A.V.1, Chumak A.G.1
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Affiliations:
- Belarusian State University
- Belarusian State Medical University
- Issue: Vol 111, No 2 (2025)
- Pages: 306-319
- Section: EXPERIMENTAL ARTICLES
- URL: https://edgccjournal.org/0869-8139/article/view/679311
- DOI: https://doi.org/10.31857/S0869813925020082
- EDN: https://elibrary.ru/UINBFY
- ID: 679311
Cite item
Abstract
Experiments were performed under urethane anesthesia on sexually mature non-pregnant female rats (n = 36). Pattern of electrical activity of the uterus in different phases of the estrous cycle, determined by the vaginal cytology (staining by Romanovsky dye), was studied. Electrohysterograms from the middle third of the left horn of the uterus were recorded using pressure bipolar electrodes. Increased excitability and conductivity of the uterus smooth myocytes occur during the stages of proestrus, estrus and metestrus, and their suppression is observed in diestrus. The maximum amplitude of motor potentials, compared to diestrus, was detected at the pro- (174 ± 17 μV) and metestrus (202 ± 20 μV) stages, while their mean frequency was high at the metestrus [4.4 (4.0; 5.0) Hz] and estrus [4.0 (4.0; 5.0) Hz)], exceeding those indicators for diestrus (86 ± 9 μV and 1.9 (1.3; 3.2) Hz approximately twice. Burst phase duration [40 (32; 50) and 36 (28; 47) s] of uterus periodic electrical activity had it maximum while rest period had it minimum [46 (40; 55) and 42 (26; 84) s] at proestrus and estrus stages which is also reflected in the high values of duty cycle – 0.46 (0.43; 0.50) and 0.45 (0.26; 0.63), respectively. Similar indicators for the diestrus stage were 27 (22; 32) and 80 (58; 124) s, 0.27 (0.18; 0.34). It is assumed that the highest excitability of the myometrium and its rhythmogenic areas during the metestrus stage, an increase in myometrium’s excitation conduction rate during proestrus and estrus, are due to an increase of electrical coupling between uterus smooth muscle cells.
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About the authors
S. A. Rutkevich
Belarusian State University; Belarusian State Medical University
Author for correspondence.
Email: rutkevitch@inbox.ru
Belarus, Minsk; Minsk
P. G. Pihul
Belarusian State University
Email: rutkevitch@inbox.ru
Belarus, Minsk
Yu. D. Panimatska
Belarusian State University
Email: rutkevitch@inbox.ru
Belarus, Minsk
V. B. Kazakevich
Belarusian State University; Belarusian State Medical University
Email: rutkevitch@inbox.ru
Belarus, Minsk; Minsk
I. A. Veres
Belarusian State Medical University
Email: rutkevitch@inbox.ru
Belarus, Minsk
A. V. Sidorov
Belarusian State University
Email: rutkevitch@inbox.ru
Belarus, Minsk
A. G. Chumak
Belarusian State University
Email: rutkevitch@inbox.ru
Belarus, Minsk
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