Adrenergic innervation of the ureters, urinary bladder, and urethra in pigs

Studies were conducted on 4 sexually mature and 4 immature pigs. Scraps of the ureters, urinary bladder, and urethra were cut with a freezing microtome. Fluorescence method of Torre and Surgeon (1976) was used to reveal the adrenergic innervation. It was found that the ureters were weakly supplied with the adrenergic nerves; most of the nerves were located in the muscular and submucosal membranes. Apex of the urinary bladder possessed the weakest innervation. More nerves were found in particular layers of the bladder corpus whereas bladder trigonum and cervix possessed numerous nerves. Adrenergic innervation of the urethra was similar to that of the urinary bladder's cervix. Adrenergic nerves were present in the serous and muscular membranes of both the urinary bladder and the urethra. Part of the nerve fibres was connected with blood vessels of the organs under study.