URETHRAL RESISTANCE AND NITRIC OXIDE CONTAINING NERVE IN RATS OF NON-INSULIN DEPENDENT DIABETES MELLITUS MODEL

초록

Introduction: Clinical studies reported that as many as 83% of all patients suffering from diabetic neuropathy have vesical dysfunction involvement as manifested by an abnormal cystometrogram and a grossly enlarged bladder. Previous investigations of bladder innervation and function led to the conclusion that bladder dysfunction in cases of diabetes mellitus is a manifestation of autonomic neuropathy. Although numerous researchers reported loss of bladder sensation and contractility based on results obtained by cystometry, there have been few investigations of the urethral opening, which has been proved the important role in the pathogenesis of other neurogenic and non-neurogenic bladder dysfunction. Nerve containing nitirc oxide(NO) has been closely linked to neurally mediated relaxation of that urethra. We evaluated the urethral resistance obtained by urodynamic study in rats of control and diabetes mellitus, and correlated the activity of n-NOS immunohistochemical staining in those rats. Materials and Methods: 1) Experimental groups and diabetes induction: 75 male Sprague-Dawley rats(38 diabetes and 37 control; 200-500 grams), breeding from birth, were included in this study. Diabetes was induced in two day-old neonates by intraperitoneal administration of streptozotocin at 90 mg/kg, freshly dissolved in sterile 0.1 M citrate buffer, which was the non-insulin dependent diabetes mellitus(NIDDM) model described by Weir. Controls were injected with the equivalent volume of citrate buffer. The experiment was done at 12, 24, 36 weeks, divided to three groups of pancreas staining(18), in vitro(18), in vivo(39) study, which had two groups of NIDDM and control. 2) Methods: A) Pancreas staining: For immunohistochemistry, we used the primary antibodies of Mouse anti-insulin and ABC-p method. B) In vivo experiment: we used the parameter of Detrusor Leak Point Pressure obtained by the urodynamic study in rats with L-nitro-arginine-methyl ester(L-NAME) and sodiu