Alterations in urinary bladder function in aging male rats

To begin to address the mechanistic basis for commonly observed urinary bladder dysfunctions in the elderly, we evaluated age‐related changes in bladder function in a rodent model. Male Fisher 344/Brown Norway (F344/BN) rats were divided into 3 groups: Young (4–6 months; n=11), Middle (15–17 months; n=17), and Old (28–30 months; n=9). Cystometric studies were performed on conscious, freely moving rats in vivo . Longitudinal bladder tissue strips were harvested for pharmacological studies in vitro . Changes in several cystometric parameters clearly indicate the presence of age‐related changes in bladder function. The main findings are summarized below. Pharmacological studies revealed that despite an age‐related increase in bladder weights, the maximal contractile response (E max ) to the muscarinic agonist, carbachol was reduced, although the sensitivity (pEC 50 ) was increased.The observed age‐related effects on bladder function recapitulate relevant aspects of the corresponding human condition. The F344/BN rat should provide a useful model for improved understanding of the mechanistic basis of age‐related bladder dysfunction (PO1 AG011370 ).