Effects of oviductal occlusion with silicone rubber on pregnancy and smooth muscle contractility of oviducts in rabbit

This study is to investigate the pregnancy and contraction of rabbit oviductal isthmicsmooth muscle after injection of a single ingredient of medical silicone rubber 0.2～0.3ml for 3 to 17 months. The restults are as follows:(1)Silicone rubber occluding rabbit oviduct had fine antifertility effect.Allrabbits in the control group were pregnant with an average of six embryos.No pregnancy occurred inbilaterally occluded group. In the unilaterally occluded group,there was no pregnancy at the occludedside: pregnancy at the control side occurred with significantly decreased number of embryos(average 1.5).(2)The oviductal smooth muscle of isthmus retained strong spontaneous contractility after occlusion,butthe amplitude of circular smooth muscle contraction decreased slightly,(3)The response of smooth mus-cle of oviductal isthmus after occlusion to exogenous NE and PGF2χ revealed no obvious change.The results indicate that good antifertility efficacy can be achieved by using a single ingredient medi-cal silicone rubber,through the blockage of oviduct and the prevention of sperms ova interaction,whilethere is no obvious effects on oviductal smooth muscle contractility.