ABSTRACT
The aim of the present study, performed on two different groups of volunteers, is to characterize the pharmacokinetics of lisinopril/hydrochlorothiazide combined tablet. After administration of high, medium and low doses of lisinopril/hydrochlorothiazide combined tablets, AUC and C(max) of two compounds both increase significantly with increase of dose. Neither normalized AUC/Dose nor C(max)/Dose has significant difference between every two tested dose groups. The similar results can be observed as for the parameters of t(max). Lisinopril and hydrochlorothiazide are both eliminated with linear characteristics. After repeated administration of lisinopril/hydrochlorothiazide combined tablets, AUC, C(max) and C(min) of lisinopril in the steady state increase. AUC and C(min) increase significantly. As for hydrochlorothiazide, AUC, C(max), C(min), and t(max) also increase in steady state. AUC and C(min) increase significantly. Administered with the test medication, lisinopril has an fluctuation index (FI) value of 2.29 and reaches a relative steady concentration. But hydrochlorothiazide has an FI value of 4.09 with relatively large fluctuating concentrations.
Subject(s)
Antihypertensive Agents/pharmacokinetics , Hydrochlorothiazide/pharmacokinetics , Lisinopril/pharmacokinetics , Adult , Antihypertensive Agents/administration & dosage , Antihypertensive Agents/blood , Area Under Curve , Asian People , Biological Availability , Cross-Over Studies , Dose-Response Relationship, Drug , Drug Combinations , Female , Humans , Hydrochlorothiazide/administration & dosage , Hydrochlorothiazide/blood , Lisinopril/administration & dosage , Lisinopril/blood , Male , Tablets , Young AdultABSTRACT
AIM: To study the effects of some bioflavonoids on the gossypol-induced hypokalemia. METHODS: The 11beta-hydroxysteroid dehydrogenase (11beta-OHSD) protein was prepared from guinea pig kidney. The activity of 11beta-OHSD with NAD as the coenzyme was measured by HPLC. The drug interaction was analysed by isobolographic method. RESULTS: The 11beta-OHSD can be inhibited by some bioflavonoids. The IC50 (95 % confidence limits) values were: quercetin 164 (79 - 341) micromol/L, morin 913 (385 - 2173) micromol/L, and naringenin 2193 (1114 - 4315) micromol/L. When the 11beta-OHSD was treated with quercetin, tangeretin, morin, naringenin plus gossypol, the combination index (CI) values were 0.92, 0.85, 0.98, and 1.01 respectively. CONCLUSION: The interaction of some bioflavonoids with gossypol might be one of the factors for gossypol-induced hypokalemia.
