Late-life enalapril administration induces nitric oxide-dependent and independent metabolic adaptations in the rat skeletal muscle.

Recently, we showed that administration of the angiotensin-converting enzyme inhibitor enalapril to aged rats attenuated muscle strength decline and mitigated apoptosis in the gastrocnemius muscle. The aim of the present study was to investigate possible mechanisms underlying the muscle-protective effects of enalapril. We also sought to discern the effects of enalapril mediated by nitric oxide (NO) from those independent of this signaling molecule.

Assessing locomotor-stimulating effects of cocaine in rodents.

Locomotor activity procedures are useful for characterizing the behavioral effects of a drug, the influence of pharmacological, neurobiological, and environmental manipulations on drug sensitivity, and changes in activity following repeated administration (e.g., tolerance or sensitization) are thought to be related to the development of an addiction-like behavioral phenotype.

Differential effects of enalapril and losartan on body composition and indices of muscle quality in aged male Fischer 344 × Brown Norway rats.

The primary purpose of the present set of studies was to provide a direct comparison of the effects of the angiotensin-converting enzyme inhibitor enalapril and the angiotensin receptor blocker losartan on body composition, physical performance, and muscle quality when administered late in life to aged rats. Overall, enalapril treatment consistently attenuated age-related increases in adiposity relative to both placebo and losartan. The maximal effect was achieved after 3 months of treatment (between 24 and 27 months of age), at a dose of 40 mg/kg and was observed in the absence of any changes in physical activity, body temperature, or food intake.

Effects of chronic fentanyl administration on physical performance of aged rats.

There is growing concern over the increasing use of opioids to treat chronic pain in the elderly primarily because of the potential increased sensitivity to the adverse side effects. Here, we use a preclinical model (male Brown Norway X F344 rats aged 12, 18, 24, and 30 months) to describe the outcome of chronic fentanyl administration (1.0mg/kg/day) on various physiological and behavioral measures.

Evaluation of prescription opioids using operant-based pain measures in rats.

Opioids are the most effective compounds available for the relief of pain, yet there are a number of side effects that are of great concern to clinicians. For example, opioids are powerful reinforcers, and the treatment of pain using opioids could lead to the development of addiction. In addition, there is an increasing body of literature demonstrating that the repeated administration of opioids could lead to a phenomenon called opioid-induced hyperalgesia (i.