Diabdetes is known to induce autonomic dysfunction and most experiment have been focused on the smooth muscle dysfunction of the urinary bladder and corpus cavernosus in the genitourinary tract. The contractile response of the vas deferens is
also
decreased in diabetic rate and this effect may cause impairment of sperm transportataion. However, few studies have been investigated the changes of contractility of the vas deferens in diabetic animals and little attention has been given to the
differences between the contractilities of the prostatic and epididymal ends of the vas deferens in diabetic rats.
In this study, the whole vas diferens was divided into two portions, prostatic and epididymal ends, and we examined the contractility of both segment ot field stimulation at various frequencies from 4 to 64 Hz for 30 sec with pulses of 1 msec
duration
at 80 V in organ bath containing modified Tyrode's solution. Both initial twitch and the last contraction after 30 sec elicited by field stimulation were compared to clarify which component was more suseptible to field stimulation in control and
diabetic rats. In the prostatic end, initial twitch was more impaired then the last contraction, which is believed that in diabetic rats, ATP(adenosine triphosphate) is more affected than NA9nordrenaline). In contrast, in the epididymal end the
last
ocntraction was more impaired than the initial twitch. In 64 Hz, initial twitch and the secondary contractions were not distinguished in the epididymal end of control end of control rats but in diabetic rats both phases were distinct. This means
that
the release of NA to field strmulation in the epeididymal end is delayed in diabetic rats.
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