Smooth muscle electromyography from rat urethra

Abstract

Electrical signals recorded from the penis have been suggested as reflecting electromyographic activity in the underlying smooth muscles. In order to verify this assertion, we manipulated the signal recorded from rat urethra surface. Stimulation of the pelvic nerve brought about a reduction of activity (965 ± 826 to 166 ± 143 µV, root mean square of the power at range 0.005-1 Hz, P = 0.008), with a significant frequencyresponse relationship (P = 0.0002). This effect was not altered by temporary closure of the aorta (P = 0.89), thus ruling out hemodynamic artifact as a possible cause of signal change during stimulation. Our findings support the assertion that the signal indeed reflects activity in smooth muscle.

The neurology of male sexual dysfunction and its investigation by clinical neurophysiological methods

“…A recent experimental study using rat spongiosal urethra showed a reduction in recorded electrical activity on unilateral stimulation of the pelvic nerve, and by clamping or leaving open the aorta, it could be shown that the activity was independent of penile erection and therefore not a haemodynamic artefact. From this it was concluded that that the recorded signal reflected activity in smooth muscle [ 95].…”