肾上腺素能神经纤维与膀胱输尿管返流关系的实验研究

Experimental studies of adrenergic fibers and vesicoureteral reflux

目的 探讨大鼠发育期膀胱输尿管返流 (VUR)与不同鼠龄及膀胱儿茶酚胺含量的关系。 方法 选择 4 5只鼠龄不同的Long Evans鼠分为 3组 ,幼鼠组 15只 ,成年鼠组 15只 ,老年鼠组15只。大鼠仰卧位 ,开腹显露两侧输尿管 ,套管针经膀胱顶穿刺 ,拔出针芯 ,排空膀胱。导管用照明灯加热并连接Haverd泵以 0 .116ml/min的速度注入膀胱亚甲蓝溶液 ,Zess外科显微镜下观察输尿管返流及尿道口尿液溢出情况。测压导管与Bentley生理压力换能器连接 ,测定VUR的发生率以及VUR发生时的膀胱压力 ,容量。放射免疫方法测定儿茶酚胺含量。 结果 幼鼠组无 1例VUR ,成年鼠组VUR的发生率为 6 0 % (9/ 15 ) ,老年鼠组VUR发生率为 4 7% (7/ 15 ) ,而膀胱儿茶酚胺含量测定显示多巴胺和肾上腺素含量在幼年时较高而随年龄增长逐渐下降。 结论 幼年大鼠膀胱的高多巴胺和肾上腺素水平可能起到了神经成熟前的代偿功能以防止VUR的出现。

Objective To evaluate the correlation between vesicoureteral reflux (VUR),age,and bladder catecholamine content in rats. Methods Forty-five Long-Evans rats were divided into three groups: fifteen were babies,fifteen were adults,and fifteen were old retired breeder rats. The animals were placed in a supine position,the peritoneal cavity was opened, both ureters were exposed to be observed under the Zess model surgical microscope.A TelcoTm striped 24 G 3/4 in.I.V.catheter placement unit was punctured into the vertex of the urinary bladder.The needle was then withdrawn and the bladder was emptied.The bladder pressure was subsequently monitored by means of a Beckman polygraph via a Bentley physiological pressure transducer.The Teflon catheter was also connected with an infusion withdrawal pump (Haverd type 936). The connective tube was warmed with a simple light bulb. Methylene blue solution (10 mg+19 ml saline) was used as a developing dye at an infusion rate of 0.116ml/min. Likewise,both ureters and the urethral orifice were carefully observed.The pressures at reflux,the pressure at leakage point were recorded.The bladder catecholamine contents were determined with a radioenzymatic assay. Results None of the baby rats showed reflux, 60%(9/15)adult rats had VUR.Dopamine and epinephrine contents were higher in baby rats and decreased as the animal aged. Conclusions High levels of dopamine and epinephrine at weaning stage could compensate to prevent VUR before nerve maturity.