title: Rapid determination and comparative pharmacokinetics of tetrahydropalmatine in spontaneously hypertensive rats and normotensive rats.
abstract: A rapid high-performance liquid chromatographic method was developed and validated for determination of tetrahydropalmatine (THP), an active component of Rhizoma Corydalis, in rat plasma. The samples were prepared using protein precipitation and separated on an Agilent XDB-C(18) column (150 × 4.6 mm, 5 µm) with the mobile phase consisting of methanol–0.1% phosphate acid solution, adjusted with triethylamine to pH 5.5 (65:35). Good linearity was found within 0.10–10.00 µg/mL of THP in rat plasma sample. The intra- and inter-day precision values were less than 10%. The developed method was successfully applied to assess the pharmacokinetics of THP in spontaneously hypertensive rats (SHR) and normotensive rats. After oral administration of a single dose of THP (60 mg/kg), the maximum plasma concentrations were 6.15 ± 2.1 and 7.54 ± 2.9 µg/mL for normotensive rats and SHR, respectively. The mean values of AUC(0–∞) of THP in SHR were 81.44 ± 45.0 µg h/mL, significantly higher (p < 0.05) than in normotensive rats (44.06 ± 19.6 µg h/mL). The t(1/2) and MRT in SHR were much longer than that in healthy Sprague–Dawley rats, indicating slow elimination of THP in SHR. The results indicated that there are some differences in pharmacokinetics of THP in SHR and Sprague–Dawley rats and it is very important to investigate the pharmacokinetic properties of drugs in pathological conditions.
authors.affiliation: Department of Pharmaceutical Analysis, School of Pharmacy, Second Military Medical University, Shanghai 200433, People’s Republic of China. hongzhy001@yahoo.com.cn
authors.forename: Zhanying
authors.initials: Z
authors.lastname: Hong
authors.forename: Guojun
authors.initials: G
authors.lastname: Cai
authors.forename: Wentao
authors.initials: W
authors.lastname: Ma
authors.forename: Jun
authors.initials: J
authors.lastname: Wen
authors.forename: Yifeng
authors.initials: Y
authors.lastname: Chai
authors.forename: Guorong
authors.initials: G
authors.lastname: Fan
mesh_terms: D000818:Animals; D019540:Area Under Curve; D001600:Berberine Alkaloids / Q000097:blood* / Q000737:chemistry / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase; D004355:Drug Stability; D005260:Female; D016014:Linear Models; D051381:Rats; D011918:Rats, Inbred SHR; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D001600:Berberine Alkaloids; C014215:tetrahydropalmatine