Adrenergic and cholinergic activity of the Japanese quail oviduct in vitro

The responses to isoprenaline, phenylephrine, and carbachol in different segments of isolated intact oviduct were studied. Smooth muscle electrical activity was recorded with suction electrodes placed, one electrode in each, in the infundibulum, proximal magnum, distal magnum, isthmus, shell gland, and vagina. The drugs were added cumulatively. Only in the magnum did isoprenaline cause a significant change in the frequency of spike discharges; the decrease was about 20%. The effects of phenylephrine were not so clear, although the frequency of the electrical activity increased 30% in the shell gland. With the exception of the infundibulum, carbachol significantly increased the frequency of the oviductal electrical activity. It was concluded that adrenergic nerves have only a minor role in controlling quail oviductal smooth muscle because the oviduct was rather insensitive to adrenergic drugs whereas the cholinergic drug carbachol caused a strong response.