Experimental Study On The Mechanism Of The Changes In The Non-insulin Dependent Diabetes Mellitus Rats' Detrusor Function

Purpose1.To find a kind of methods to manufacture the non-insulin dependent diabetes mellitus rats model.2.To investigate the changes of the NIDDM rats' detrusor function and provide the data for the clinical urodynamic diagnosis.3.To discover the pathophysiology mechanism of the damage in the NIDDM rats' detrusor.Material and MethodsThe present study is composed of the following four sub-article: Part one: To manufacture and validate the model rats on non-insulin dependent diabetes mellitus.147 Wistar rats born two days were divided into two groups. The NIDDM group rats underwent intraperitoneal inject with 90mg/kg streptozotocin (STZ). While they have ablaction they had inject with 25mg/kg streptozotocin(STZ) again. Then these rats were fed with the diets enriched with sucrose (20% w/w) and lard(18%.w/w)and yolk powder(3%,w/w).Another group served as controls. Part two: Experimental study of excitability and autorhthmicity and contraction /relaxation in urinary bladder of NIDDM rats The NIDDM group rats and controls group rats had been examined by urodynamic testing machine after they have been fed special diats12th and 24th weeks. At 4th/8th/12th/16th/20th/24th weeks they had been fed special diets, the diabetes rats and controls rats tested by detrusor strips in vitro. Part three: Experimental study of succinate dehudrogenase change and ultra-structural change of mitochondrion of detrusor in diabetes ratswhile they have ablaction and after 4th/8th/12ve/16th/20th/24th weeks they had been fed special diets, the diabetes rats and controls rats had been killed ,and the bladder make into homogenate. Determined the activity of the succinate dehydronase by chromatometry . The ultrastructures of mitochondrion in detrusor cell of each rat were examined after the 4th/12ve/24th week they had been fed the special diets.Part four: The changes of adenosine-triphosphatase activity in bladder homogenate and cytosol-free Calcium concentration in single bladder smooth muscle cells from normal and diabetic rats.The adenosine-triphosphatase activity had been examinated by chromatometry. The effect of diabetes mellitus on intracellular calcium concentration was measured in single rat bladder smooth muscle cells using the fluorescent calcium indicator dye Fura-2/AM at rest situation.Result 1.The model on non-insulin-dependent diabetes mellitus is successful.2.At the early stage, the excitability of diabetes rats was depressed. The contraction and relaxation of diabetes rats were lower than the rats in controls group. The autorhthmicity of the diabetes rats was increased before 22nd weeks, then decreased than the controls rats. The bladder weight /residual urine and bladder compliance were increased on diabetes rats. 3.The activity of the succinate dehydronase (SDH) decreased at the in the initial stage of NIDDM rats. The damage of mitochondrion's ultrastructures in detrusor cell became manifest by progression.4. The adenosine-triphosphatase activity had been decreased at the initial stage by the effect of diabetes mellitus. The intracellular calcium concentration in single rat bladder smooth muscle cells had no significant difference in the initial stage at rest situation. After 20 weeks they fall ill, The intracellular calcium concentration in single rat bladder smooth muscle cells had increased than control rat's.Conclusion 1.The excitability depressed is the first change in diabetes rats' detrusor. The autorhthmicity had also changed at the early stage .The damage of contraction and the relaxation maybe the reasons of the compliance change on the diabetes rats' bladder.2.Detrusor contraction was impaired in the early stage of diabetes. The mitochondrion destroyed and the detrusor metabolism dysfunction should been one of the reasons. 3.Intracellular calcium overload occurred latter than the dysbolism.4.To control the dysbolism and use ATP or the calcium antagon maybe a good treatment of the diabetic cystopathy.