AIMS To determine the effect of prostatic radiation therapy (RT) on bladder contractility and morphology, and axon, or neuron profiles within the detrusor and major pelvic ganglia (MPG) in male rats. METHODS Male Sprague-Dawley rats (8 weeks) received a single dose of prostatic RT (0 or 22 Gy). Bladders and MPG were collected 2- and 10-weeks post-RT. Detrusor contractile responses to carbachol and electrical field stimulation (EFS) were measured. Bladders were stained with Masson's trichrome, and antibodies for nonspecific neuronal marker, cholinergic nerve marker choline acetyltransferase (ChAT), and alpha-smooth muscle actin. MPG gene expression was assessed by quantitative polymerase chain reaction for ubiquitin carboxy-terminal hydrolase L1 (Uchl1) and Chat. RESULTS At 2 weeks post-RT, bladder smooth muscle, detrusor cholinergic axon profiles, and MPG Chat gene expression were increased (p