Impulses in smooth muscle of rabbit deferent duct

Abstract

Action potentials and contractions were recorded from excised rabbit deferent ducts. Tissues from normal animals showed slow electrical waves accompanying local contractions. Castration caused spontaneous activity to increase. Deferent ducts from three of eight castrated animals showed propagation of evoked potentials; such activity was inhibited by testosterone and intensified by estradiol. Estradiol rendered deferent ducts from normal rabbits as active as those from castrated ones. Evoked responses in preparations from estrogen-treated animals were propagated at a mean velocity of 3.14 cm/sec (sd 1.98). Velocity was randomly variable within as well as between preparations. Impulse width was less than 5.0 mm but greater than 1.6 mm. Since the depolarized area spanned many cells it is concluded that some form of intercellular continuity exists.