Assessment of myoelectrical signal parameters in estrogen, progesterone, and human chorionic gonadotropin administered in nonpregnant rat myometrium after ovariectomy.
OBJECTIVE
To investigate the correlation of myoelectrical signals with spontaneous contractile events and physiological states in the nonisolated uterine horn of rats.


METHODS
In vivo uterine myoelectrical activity recording study.


METHODS
Animal and pharmacology laboratory at Inonu University.


METHODS
Thirty-six female Wistar albino rats.


METHODS
Six animals were not castrated and served as a sham-operated control group; the other 30 were ovariectomized (OVX) and put into groups: unbiased OVX subjects, estrogen (E)-biased OVX subjects, P-biased OVX subjects, E-plus-P-biased OVX subjects, and hCG-biased OVX subjects. An MP100 A-CE was used for data acquisition, and a personal computer was used for processing.


METHODS
Besides the temporal, spectral, and joint time-frequency (spectrotemporal) analysis, some quantitative measures such as standard deviation and mark to space power ratios of myoelectrical signals were measured.


RESULTS
Progesterone, E, and hCG administration down-regulated the power and contraction frequency of the uterine electrical signal. The spectral concentrations that occurred around the 0.9, 0.35, and 0.7 Hz frequency ranges may be distinguishing characteristics for P, E, and hCG, respectively.


CONCLUSIONS
Based on the obtained results, uterine contractions change with ovariectomy and administration of hormones. Progesterone, E, and hCG particularly prolong the quiescent periods of the uterus by reducing the frequency of uterine contractions as well as the power of the myoelectrical activity. Individual or combined use of P, E, or hCG might favor quiescence of the uterine muscle and the maintenance of pregnancy.
Celik
Onder
O
Department of Obstetrics and Gynecology, Inonu University Medical Faculty, Malatya, Turkey. oncelik@inonu.edu.tr
Hascalik
Seyma
S
Tagluk
M Emin
ME
Elter
Koray
K
Parlakpinar
Hakan
H
Acet
Ahmet
A
D000818:Animals; D006063:Chorionic Gonadotropin / Q000008:administration & dosage*; D004576:Electromyography; D004966:Estrogens, Conjugated (USP) / Q000008:administration & dosage*; D005260:Female; D005300:Fertility Agents, Female / Q000008:administration & dosage*; D006801:Humans; D008564:Membrane Potentials / Q000187:drug effects; D009215:Myometrium / Q000187:drug effects*; D010052:Ovariectomy; D011374:Progesterone / Q000008:administration & dosage*; D051381:Rats; D017208:Rats, Wistar; D012815:Signal Processing, Computer-Assisted; D013997:Time Factors; D014590:Uterine Contraction / Q000187:drug effects*
D006063:Chorionic Gonadotropin; D004966:Estrogens, Conjugated (USP); D005300:Fertility Agents, Female; D011374:Progesterone