Cocaine- and amphetamine-regulated transcript-like immunoreactivity (CART-LI) in intramural ganglia of porcine urinary bladder trigone

Although the expression pattern of cocaine- and amphetamine-regulated transcript (CART) has been studied in several porcine tissues, it is notable that no data are available on CART expression in the lower urinary tract. In order to map and determine the neurochemical code of CART-like immunoreactivity in the intramural ganglia of the porcine urinary bladder trigone, cryostat sections were immunohistochemically double-stained for CART and HuC/D, as well as for substance P (SP), calbindin, somatostatin and pituitary adenylate cyclase-activating peptide (PACAP). In the ganglia of the urinary bladder trigone, immunoreactivity to CART was detected both in numerous nerve fibres and in minor subpopulation of HuC/D-positive neuronal cell bodies (2.7 +/- 0.8%). Neither CART-immunoreactive (IR) nerve fibres, nor CART-IR ganglionic neurons showed simultaneous expression of somatostatin, calbindin and SP. In a substantial proportion of CART-IR neurons (but not nerve fibres) co-localization with PACAP was found. This data suggest that CART present in nervous structures of the porcine urinary bladder may have a role in the parasympathetic regulation of several urinary bladder functions.