Ciprofloxacin blocked enterohepatic circulation of diclofenac and alleviated NSAID-induced enteropathy in rats partly by inhibiting intestinal β-glucuronidase activity.

Aim: Diclofenac is a non-steroidal anti-inflammatory drug (NSAID), which may cause serious intestinal adverse reactions (enteropathy). In this study we investigated whether co-administration of ciprofloxacin affected the pharmacokinetics of diclofenac and diclofenac-induced enteropathy in rats.

Methods: The pharmacokinetics of diclofenac was assessed in rats after receiving diclofenac (10 mg/kg, ig, or 5 mg/kg, iv), with or without ciprofloxacin (20 mg/kg, ig) co-administered.

Unconjugated bilirubin elevation impairs the function and expression of breast cancer resistance protein (BCRP) at the blood-brain barrier in bile duct-ligated rats.

Aim: Liver failure is associated with dyshomeostasis of efflux transporters at the blood-brain barrier (BBB), which contributes to hepatic encephalopathy. In this study we examined whether breast cancer resistance protein (BCRP), a major efflux transporter at the BBB, was altered during liver failure in rats.

Methods: Rats underwent bile duct ligation (BDL) surgery, and then were sacrificed after intravenous injection of prazosin on d3, d7 and d14.

Differential effects of pravastatin on the pharmacokinetics of paroxetine in normal and diabetic rats.

1. Diabetes is often accompanied with depression and hypercholesterolemia. It is possible that paroxetine and pravastatin are co-administered to diabetic patients.

Chronic administration of caderofloxacin, a new fluoroquinolone, increases hepatic CYP2E1 expression and activity in rats.

Aim: Caderofloxacin is a new fluoroquinolone that is under phase III clinical trials in China. Here we examined the effects of caderofloxacin on rat hepatic cytochrome P450 (CYP450) isoforms as well as the potential of caderofloxacin interacting with co-administered drugs.

Methods: Male rats were treated with caderofloxacin (9 mg/kg, ig) once or twice daily for 14 consecutive days.

Laminaria japonica increases plasma exposure of glycyrrhetinic acid following oral administration of Liquorice extract in rats.

The present study was designed to investigate the effects of Laminaria japonica (Laminaria) on pharmacokinetics of glycyrrhetinic acid (GA) following oral administration of Liquorice extract in rats. Following oral administrations of single-dose and multi-dose Liquorice extract and Liquorice-Laminaria extract, respectively, plasma samples were obtained at various times and the concentrations of GA, liquiritigenin, and isoliquiritigenin were measured by LC-MS. The effects of Laminaria extract on pharmacokinetics of GA were also investigated, following single-dose and multidose of glycyrrhizic acid (GL).

High-fat diet enhanced retinal dehydrogenase activity, but suppressed retinol dehydrogenase activity in liver of rats.

Evidence has shown that hyperlipidemia is associated with retinoid dyshomeostasis. In liver, retinol is mainly oxidized to retinal by retinol dehydrogenases (RDHs) and alcohol dehydrogenases (ADHs), further converted to retinoic acid by retinal dehydrogenases (RALDHs). The aim of this study was to investigate whether high-fat diet (HFD) induced hyperlipidemia affected activity and expression of hepatic ADHs/RDHs and RALDHs in rats.

Decreased exposure of simvastatin and simvastatin acid in a rat model of type 2 diabetes.

Aim: Simvastatin is frequently administered to diabetic patients with hypercholesterolemia. The aim of the study was to investigate the pharmacokinetics of simvastatin and its hydrolysate simvastatin acid in a rat model of type 2 diabetes.

Methods: Diabetes was induced in 4-week-old rats by a treatment of high-fat diet combined with streptozotocin.

Co-administration of paroxetine and pravastatin causes deregulation of glucose homeostasis in diabetic rats via enhanced paroxetine exposure.

Aim: Clinical evidence shows that co-administration of pravastatin and paroxetine deregulates glucose homeostasis in diabetic patients. The aim of this study was to verify this phenomenon in diabetic rats and to elucidate the underlying mechanisms.

Methods: Diabetes mellitus was induced in male SD rats by a high-fat diet combined with a low-dose streptozotocin injection.

Aggravation of clozapine-induced hepatotoxicity by glycyrrhetinic acid in rats.

Clozapine (CLZ) was reported to be associated with hepatotoxicity. Glycyrrhetinic acid (GA) has a liver protective effect. Our preliminary experiments showed that GA aggravated rather than attenuated CLZ-induced hepatotoxicity in primary cultured rat hepatocytes.

Validated LC-MS/MS assay for quantitative determination of deoxypodophyllotoxin in rat plasma and its application in pharmacokinetic study.

A rapid and sensitive liquid chromatography/tandem mass spectrometry method was developed and validated for the quantification of deoxypodophyllotoxin (DPT) concentration in rat plasma with diazepam as internal standard (IS). DPT and IS were extracted with ethyl acetate, and the chromatographic separation was accomplished by using a Waters Symmetry C18 analytical column (2.1mm×150mm, 5μm) with a mobile phase consisting of acetonitrile and deionized water (70:30, v:v) containing 0.