The Effect Of Caffeine On Urodynamic Indexes And Pathological Observation Of Early And Late Diabetic Bladder Rats

Objective:To study the changes of diabetic bladder from compensatory to decompensation in rats.This study explored the changes of bladder function in early and late diabetic rats and the effect of caffeine intervention on the function of urine after the intervention of urodynamics.Methods:80 SD rats were randomly divided into blank control group（group NC）,negative control group（group COF）,diabetes group（group DM）and caffeine treatment group（group CT）,with 20 rats in each group.Each group was divided into two subgroups in 8 and 16 weeks according to the time of modeling.Among them,diabetes and caffeine treatment group were induced by single intraperitoneal injection of streptozotocin.The weight and blood sugar of the rats were measured regularly.Urodynamic examinations and bladder related indexes were performed in rats at 8 and 16 weeks.The results were as follows:the maximum urinary bladder pressure（Pmax）,urinary interval（IVT）,maximum bladder capacity（MBC）residual urine volume（PVR）,bladder wet weight（BWW）and bladder index（wet weight/weight）.After the completion of the experiment,pathological examination of the bladder was performed and the results were analyzed.Results:The interval of urination of rats in the 8 week diabetes group was 57.78 ±9.4s,and the time of urination was 92.70±14.23 compared with that of the blank control group,and time was shorter.There was no difference in bladder pressure during urination.The maximum pressure of bladder in the 16 weeks diabetic rats was 2.45±0.35kpa,and the interval of urination was 139.70±23.43.The maximum pressure of bladder was 4.53±0.36kpa and the interval of urination was 89.20±10.02s in the blank control group.The pressure decreased obviously and the time was obviously prolonged,the difference was statistically significant.At 8 weeks,the time interval between the caffeine treatment group was 74.13±11.87s,the maximum bladder capacity was 1.60±0.10ml,and the residual urine volume was 0.32±0.07ml.The micturition interval of the diabetic group was 57.78±9.44s,the maximum bladder capacity was 1.43±0.13ml,and the residual urine volume was 0.51±0.08ml.Compared with the two groups,the interval of urination in the caffeine treatment group increased significantly,the maximum bladder capacity increased,and the residual urine volume decreased,and the difference was statistically significant（P<0.05）.The difference of maximum pressure of bladder was not statistically significant.At 16 weeks,the maximum bladder pressure in the caffeine treatment group was 3.44±0.23kpa,the interval of urination time was 119.22±11.44s,the maximum bladder capacity was 3.32±0.47ml,and the residual urine volume was 1.10±0.24ml.The maximum bladder pressure in the diabetic group was 2.45 ±0.35kpa,the interval of urination time was 139.70±23.43s,the maximum bladder capacity was 4.64±0.36ml,and the residual urine volume was 2.41±0.26ml.In the two groups,the maximum pressure of bladder in the caffeine treatment group was significantly increased,the interval of urination was shortened,the maximum bladder capacity was reduced,and the residual urine volume decreased,the difference was statistically significant（P<0.05）.The results of pathological section HE staining and Masson staining showed that the detrusor layer in the bladder tissue of the diabetic group was thickened,irregular in shape,disorder of muscle cells and loose structure in the diabetic group.The caffeine treatment group had a certain improvement compared with the diabetic group.Conclusion:the urodynamic performance of diabetic rats in the early and late stage of diabetes is different,in the early stage,the main manifestation is overactivity of the bladder,and the late stage is mainly characterized by low bladder activity.Caffeine can improve the dysfunction of urination in early and late diabetic rats.In the early stage,the main manifestation is to relieve the bladder unstable contraction and reduce the number of urination,and the late stage is mainly to increase the contractile force of the bladder and assist the urination.This may be related to the reduction of bladder myogenic and peripheral nerve injury caused by caffeine.