ABSTRACT
Spontaneous bursts of action potential occurring in the ovarian and cervical horn areas as well as in uterine corpus were investigated in non-pregnant rats. The main characteristics of spikes registered simultaneously from the selected active regions under normal conditions - the frequency, amplitude, rise-rate, rise-time and half-width of peaks, were analyzed by complex electrophysiological and morpho-histochemical studies. The ovarian horn area generates high-amplitude spikes that significantly exceed the magnitude of spikes in two other areas. There are small differences between the frequency values in the above-mentioned rhythmogenic areas. The peak rise-rates are the greatest in the ovarian horn area. On the contary, the peak rise-times and the peak half-widths had the smalles values here. It is concluded that there is a significant difference between the values of activity parameters in the ovarian horn area and two other pacemaker areas localized rather close to each other. Analysis of the morphological and histochemical data revealed the greatest aggregation of functionally active cells between the myometrium and serosa in the ovarian horn area. In the cervical horn area and uterine corpus no focal accumulations of these cells were found. Thus, the morphological findings confirmed the electrophysiological results.