OBJECTIVE:To prepare tamsulosin hydrochloride sustained-released tablets and to investigate the in vitro drug release feature and mechanism of the tablets.METHODS:Tamsulosin hydrochloride sustained-released tablets were prepared with HPMC as matrix.The effects of multiple factors on the in vitro drug release rate were evaluated with accumulative release rate as index,and the slow release feature was compared between the sustained tablets and the common tablets.RESULTS:The drug release rate was predominantly influenced by the amount of HPMC and the tablet compressing pressure,and the optimum values of the two were 25% and 8kg～11kg,respectively.The accumulative release rates of the sustained tablets and the common tablets at 0.5h were 10% and 50%,respectively.CONCLUSIONS:The sustained-release tablets had a better sustained release efficacy as compared with common tablets,and the drug release feature of the sustained tablets was the synergistic action of the tamsulosin hydrochloride diffusion and matrix degradation and the release pattern obeyed non-Fick diffusion mechanism.

Aim To study the effect of pectin-adriamy-cin conjugate ( PAC) on cardiac toxicity .Methods 50 female SD rats were randomly divided into 5 groups with 10 animals in each group .Adriamycin ( ADM ) group received 3 mg? kg -1 , ip, every other day for 6 times.PAC group received ADM equivalent 1.5,3 and 6 mg? kg -1 , ip, every other day for 6 times.Control group received normal saline parallel to ADM .Rats were sacrificed and the echocardiogram , cardiac en-zymes , the oxidative stress levels in myocardial cells and histopathological changes after 48 h administration were detected.S180 ascites tumor bearing mice models were established to investigate the antitumor activity of PAC.Results The survival rate of ADM group was 50% and that of PAC each group was 100%.PAC could significantly increase body weight ,heart index and immune index and increase HR ,EF,FS,reduce LVIDd, LVIDs.PAC could also significantly increase the AST , LDH, CK, CK-MB level in serum .GSH-Px and SOD activities of PAC group were significantly increased and MDA contents were reduced , and histopathological changes decreased .PAC could effectively inhibit the growth of tumor cells and extend the survival period of mice.Conclusion PAC induces a significant reduc-tion in cardiotoxicity by increasing survival rate , im-mune and cardiac function , improving cardiac en-zymes ,oxidative stress and myocardial cell injury , and also PAC has obvious antitumor effect .