Hyalinization of the pyloric stomach in CD-1 mice following oral (dietary) administration of the corticosteroid agonists mometasone furoate, budesonide, and flunisolide.

The purpose of this study was to compare the toxicity of three marketed corticosteroid receptor agonists (mometasone furoate, budesonide, or flunisolide) to the stomach of female CD-1 mice following oral administration via the diet for up to 52 weeks, with a 16-week recovery period (budesonide and flunisolide). A range of tissues was examined by light microscopy, accompanied by clinical pathology measurements to assess anticipated corticosteroid effects as a surrogate marker of systemic drug exposure. Microscopic changes seen in the stomach with each corticosteroid included pyloric hyalinization.

Eosinophilic inclusions in rat Clara cells and the effect of an inhaled corticosteroid.

Large eosinophilic cytoplasmic inclusions (ECIs) are occasionally seen in untreated rat Clara cells. Following inhalation exposure to a corticosteroid, the number of ECIs was increased. This is the first histopathological description of rat ECIs and attempted characterization by immunohistochemistry, in situ hybridization, and electron microscopy.

A cohort study of telomere and telomerase biology in cats.

Objective: To investigate telomere lengths in tissues of domestic shorthair (DSH) cats of various ages, evaluate the relationship between telomere length and age of cats, and investigate telomerase activity in the somatic tissues of cats.

Sample Population: Tissues obtained from 2 DSH cats and blood samples obtained from 30 DSH cats.

Procedure: DNA isolated from blood cells and somatic tissue samples was subjected to terminal restriction fragment (TRF) analysis to determine mean telomere repeat lengths.

Telomere lengths in dogs decrease with increasing donor age.

In vitro and in vivo studies of human tissues have demonstrated telomeric attrition with age and have linked this attrition to cellular senescence and aging. Telomere studies in canine subjects have not thus far consistently uncovered the same pattern of telomere attrition that would be expected because of the end replication problem. In this report we describe the investigation of telomere lengths in a broad age range of dogs from three different breeds: the Labrador Retriever, Miniature Schnauzer and Beagle.