Laurent U B, Fraser J R, Laurent T C
Department of Ophthalmology, University of Uppsala, Sweden.
Exp Eye Res. 1988 Jan;46(1):49-58. doi: 10.1016/s0014-4835(88)80092-7.
An experimental technique to study the turnover of hyaluronan in the anterior chamber in single animals has been developed. It is based on the fact that circulating hyaluronan labelled with tritium in the acetyl group is rapidly taken up by the liver and degraded to tritiated water. 3H-labelled hyaluronan was mixed with high concentration, high molecular weight hyaluronan (Healon) and injected into the anterior chamber of rabbits. The concentration of tritiated water in blood plasma was followed for up to 13 days. An initial rise of radioactivity in the blood was followed by an exponential decrease. From the exponential disappearance it was possible to calculate the rate of turnover of water in the body. This was used to correct the initial rise of tritium for water losses. After this correction the appearance of radioactive water in blood corresponded to the disappearance of hyaluronan from the eye plus a 45 min time-lag due to the catabolism in the liver. Using this technique it was found that trace amounts of radioactive hyaluronan and 0.055 ml and 0.2 ml of 1% hyaluronan exhibited half-lives in the anterior chamber of 1.5, 7 and 13 hr respectively. When the same technique was used for subcutaneously and intramuscularly injected hyaluronan half-lives of 50 and 30 hr, respectively, were recorded.
已开发出一种用于研究单只动物前房透明质酸周转率的实验技术。该技术基于这样一个事实，即乙酰基中标记有氚的循环透明质酸会迅速被肝脏摄取并降解为氚化水。将3H标记的透明质酸与高浓度、高分子量的透明质酸（Healon）混合，并注入兔的前房。对血浆中氚化水的浓度进行了长达13天的跟踪。血液中放射性最初升高，随后呈指数下降。根据指数消失情况，可以计算出体内水的周转率。这被用于校正氚因水分流失而产生的初始升高。经过这种校正后，血液中放射性水的出现与透明质酸从眼中的消失相对应，再加上由于肝脏中的分解代谢而产生的45分钟时间延迟。使用该技术发现，痕量放射性透明质酸以及0.055毫升和0.2毫升1%的透明质酸在前房中的半衰期分别为1.5小时、7小时和13小时。当将相同技术用于皮下和肌肉注射透明质酸时，记录到的半衰期分别为50小时和30小时。
