Greger R, Lang F, Deetjen P
Pflugers Arch. 1975 Jun 26;357(3-4):201-7. doi: 10.1007/BF00585975.
Renal excretion of allantoin was measured by tracer techniques. After injection of 2-C14 urate and H3 inulin, clearances of allantoin and inulin were measured and both proximal and distal tubules were micropunctured. In confirmation of earlier results 2-C14 urate injected into an intact animal is very rapidly converted to C14 allantoin: after 15 min more than 90% of urinary tracer is present as allantoin. It was further observed that 1) allantoin clearance is essentially identical with inulin clearance over a wide range of urine flows; 2) no net transport of allantoin occurs in either proximal or distal tubules. Clearly allantoin is handled by the rat kidney like inulin. The total excretion of filtered allantoin unlike that of filtered urate provides an easy and effective mechanisms for animals possessing the enzyme uricase to dispose of their purine loads.
采用示踪技术测定尿囊素的肾排泄。注射2-C14尿酸盐和H3菊粉后，测量尿囊素和菊粉的清除率，并对近端和远端肾小管进行微穿刺。为证实早期结果，向完整动物体内注射的2-C14尿酸盐会迅速转化为C14尿囊素：15分钟后，超过90%的尿中示踪剂以尿囊素形式存在。进一步观察到：1）在很宽的尿流范围内，尿囊素清除率与菊粉清除率基本相同；2）近端或远端肾小管均未发生尿囊素的净转运。显然，大鼠肾脏对尿囊素的处理方式与菊粉相同。与滤过尿酸盐不同，滤过尿囊素的总排泄为拥有尿酸酶的动物提供了一种简单有效的机制来处理其嘌呤负荷。
