Atropine sensitivity of the rat urinary bladder during nerve degeneration

The pressure response of the rat urinary bladder to electrical stimulation of the pelvic nerve at a low stimulation frequency was found to be almost completely atropine resistant. However, the response to stimulation of the degenerating pelvic nerve 20-30 h after section of the nerve postganglionically using maximal stimulation frequency was totally abolished by atropine or the parasympatholytic agent Hoechst 9980. The responses were not affected by hexamethonium or dihydroergotamine, but were potentiated by eserine. The non-adrenergic portion of the bladder response to stimulation of the degenerating hypogastric nerves was also abolished by atropine or Hoechst 9980. It is concluded that the transmitter activating the detrusor muscle at stimulation of the pelvic nerve or the non-adrenergic part of the hypogastric nerve probably is acetylcholine.