Characterization of the adrenergic beta-receptor in the urinary bladder of man and cat

The corpus-fundus of the urinary bladder of man and cat was studied in vitro with respect to type of beta-adrenergic receptors. In both species beta-adrenergic stimulation produced marked relaxation but species differences were apparent. In the cat bladder only beta1-receptors were found. In the human bladder the beta-receptors had neither beta1- nor beta2-characteristics. It is suggested that the beta-adrenergic receptors in the corpus-fundus of the human bladder are of a third type.