[Pharmacokinetic analysis of lactosaminated human growth hormone and human growth hormone]

This study was undertaken to explore and compare the pharmacokinetic features of lactosaminated human growth hormone(hGH-L) and human growth hormone (hGH). Radioimmunoassay (RIA) technique was used. After mice were intravenously injected with hGH-L, their blood and liver samples were collected and handled. The blood drug concentration and liver drug concentration were determined using RIA technique. Then the pharmacokinetic parameters were obtained by analysing the curves of blood drug concentration-time and liver drug concentration-time. hGH was determinated with the same methods. The results showed that the area under curve (AUC) of blood drug concentration-time curve of hGH-L was 32,686.90, the mean remain time (MRT) of hGH-L in blood was 21.37 minutes, but the AUC of blood drug concentration-time curve of hGH was 36,913.08 and the MRT of hGH in blood was 24.98 minutes. Therefore, in blood, the uptake of hGH-L was less than that of hGH, the removal of hGH-L was faster than the removal of hGH. In liver, for hGH-L, the half-time of distribution (t1/2 alpha) was 1.84 minutes, the half-time of removal(t1/2 beta) was 11.09 minutes, the AUC of liver drug concentration-time curve was 17,621.9; for hGH, the t1/2 alpha was 2.11 minutes, the t1/2 beta was 75.65 minutes, the AUC of liver drug concentration-time curve was 12,148.2. Therefore, in liver, the uptake of hGH-L was more than that of hGH, the distribution and removal of hGH-L were faster than those of hGH. Therefore, the pharmacokinetic features of hGH-L was better than the feature of hGH.