Gastric damage in the rat with nitrogen-containing bisphosphonates depends on pH.

Background: The use of nitrogen-containing bisphosphonates (N-BPs) has been reported to be associated with gastrointestinal intolerance. The fasted, indomethacin-treated rat provides a model for assessing the gastrointestinal effects of these compounds.

Aims: The aims of this study were to elucidate the effect of pH on N-BP-induced gastric damage, and to evaluate the structure-activity relationship between N-BP anti-resorptive and gastric effects.

Musk xylene induces and inhibits mouse hepatic cytochrome P-450 2B enzymes.

The purpose of this work was to characterize the effects of musk xylene on mouse hepatic microsomal enzyme activities. Male B6C3F1 mice were dosed for 7 days at 0 or 200 mg musk xylene/kg after which microsomes were prepared. Musk xylene treatment increased liver weight by 40%, caused hepatocellular hypertrophy and increased total cytochrome P-450 2-fold over control.

Effect of bleeding site on clinical laboratory testing of rats: orbital venous plexus versus posterior vena cava.

We sought to determine if there were any differences in the results of clinical laboratory tests between blood samples collected from the orbital venous plexus and the posterior vena cava of adult male rats. Thirty healthy adult male Sprague Dawley rats were anesthetized by ether inhalation, and blood samples were collected successively from the orbital venous plexus (OVP) and the posterior vena cava (PVC) for hematologic (n = 10), serum chemistry (n = 10), and coagulation (n = 10) analyses. The prothrombin and partial thromboplastin times of samples from the OVP were prolonged (17% and 288%, respectively) when compared with samples from the PVC.

Effects of nitrofurantoin on the primary and secondary reproductive organs of female B6C3F1 mice.

The National Toxicology Program (NTP) has reported female mice fed high doses of Nitrofurantoin (NFT) were found to have ovarian atrophy as diagnosed histologically and increased benign ovarian tumors after 24 months of exposure (30). This result contrasts with 4 other recent carcinogenicity assays in rodents with NFT, all with no evidence of an ovarian effect. An extensive database documents benign tubular adenomas develop secondary to ovarian atrophy in many mouse strains, including B6C3F1.

A two-generation reproductive and developmental toxicity study of sucrose polyester.

Sucrose polyester (SPE) is a mixture of hexa-, hepta- and octa-esters of fatty acids with sucrose, and has physical and organoleptic properties similar to those of conventional dietary fats. Because SPE is neither absorbed nor metabolized it forms a bulk lipid phase in the small intestine, resulting in effects on the absorption and enterohepatic circulation of lipid-soluble materials, such as cholesterol and fat-soluble vitamins. Such effects could potentially alter the physiology of animals to the extent of interfering with reproduction and/or the normal development of the embryo/foetus.