| Abstrakt: |
In the previous study (Talo and Brundin, 1971) it was found in the estrogen-treated castrates that electric activity originating in the discrete region around the ampullary-isthmic junction, propagated with high velocity and triggered regular intraluminal pressure cycles of high amplitude and rapid rate of rise. In contrast, the present results showed that in the untreated and estrogen- and progesterone-treated castrates pacemaker activity was not localized, conduction was slow and limited, the intraluminal pressure cycles were of irregular and complex shape with slow rate of rise and often with low amplitude. Apparently, in the isthmus of the rabbit oviduct, as in the uterus, the conduction of the electric activity between distant regions is promoted by estrogen and disturbed or suspended by estrogen deficiency, or progesterone treatment in combination with estrogen. Variations in the generation and propagation of the electric activity suggest that hormonal control of the activity pattern could be one important mechanism in the regulation of the egg transport. |
