Abstract
This experimental study was designed and carried out in order to investigate the participation of the collagen and muscular tissues on the viscoelastic properties of the bladder wall. Sixty-five adult male mongrel dogs were utilized. These animals were divided into 5 groups: control group (n = 10); dogs (n = 10) receiving 2.5 mg/kg atropine (cholinergic antagonist); dogs (n = 10) receiving 0.7mg/kg verapamil (calcium extracellular inflow blocker); dogs (n = 10) receiving 0.1 mg/kg/min nitroprusside (intracellular calcium blocker), and dogs (n = 25) receiving EGTA (a calcium-chelating agent) at increasing doses from 90 to 450 mg/kg. Based on a mathematical model, we have demonstrated that: (1) the collagen component is responsible for the elastic properties; (2) the muscle component is responsible for the viscoelastic properties; (3) the viscoelastic properties have an active element which is affected by calcium total depletion, and (4) such viscoelastic properties are not dependent on cholinergic stimulation.