Biochemical characterization of the rabbit urinary bladder base and body

Abstract

AbstractFunctionally, the urinary bladder can be divided into two sections: the bladder body and bladder base. Pharmacologically, the bladder body responds to a greater extent than the bladder base to cholinergic agonists (contraction), beta‐adrenergic agonists (relaxation), and purinergic agonists (contraction), whereas the bladder base responds to a greater extent than the bladder body to alpha‐adrenergic agonists (contraction). The autonomic receptor density parallels the pharmacological response; that is, the bladder body contains higher densities of muscarinic cholinergic and beta‐adrenergic receptors than the bladder base, whereas the base contains a higher density of alpha‐adrenergic receptors. The purpose of this present study was to compare a variety of biochemical factors between the rabbit urinary bladder base and body.Sections of rabbit bladder body and base were rapidly dissected and frozen in liquid nitrogen. Tissue concentrations of DNA, RNA, hydroxyproline, lipids, glycogen, cyclic AMP, CP, ATP, ADP, and AMP were determined. The results demonstrated that the bladder base contained a 34% greater concentration of DNA, whereas the bladder body contained a 127% greater concentration of RNA. The bladder base contained 39.6% and 36% greater concentrations of hydroxyproline and glycogen, respectively. The concentration of lipids, cyclic AMP, and adenine nucleotides was equal in the two areas. The observed differences between bladder body and base may be related to the significantly greater work (energy utilized to actively expel urine) performed by the bladder body.