Modulatory effect of sildenafil in diabetes and electroconvulsive shock-induced cognitive dysfunction in rats.
Journal Title: Pharmacological Reports - Year 2006, Vol 58, Issue 3
Abstract
The nitric oxide/guanylyl cyclase, cyclic guanosine monophosphate/phosphodiesterase 5 (NO/cGMP/PDE5) pathways play a key role in physiological and pathological situations, such as synaptic plasticity, learning and memory formation, diabetic gastropathy and neuropathy, long-term potentiation (LTP), epilepsy, cerebral ischemia, and neurodegenerative diseases. Several studies have demonstrated the alteration of NO-cGMP pathway in cognitive impairment. The present study was aimed to study the effectof sildenafil, a PDE5 inhibitor on diabetes and electroconvulsive shock (ECS)-induced cognitive dysfunction in rat using one-trial step-through type of passive avoidance and elevated plus maze task. Diabetic and ECS-treated rats showed poor learning performance in step-through passive avoidance and plus-maze task. Acute administration of sildenafil significantly reversed the diabetes and ECS-induced retention deficits in both the test paradigms. Sildenafil also significantly improved the cognitive performance in young rats in both the paradigms. Furthermore, L-NAME, a non-selective NOS inhibitor and methylene blue, aguanylate cyclase inhibitor blocked the effect of sildenafil. The results thus suggest that cognitive impairment might be due to the modulatory effect of nNOS or PDE5 enzyme on cGMPlevels. Moreover, sildenafil-induced reversal of cognitive impairment suggests the protective role of PDE5 inhibitors in neurodegenerative disorders.
Authors and Affiliations
Chandrashekhar Patil, Vijay Singh, Shrinivas Kulkarni
Cytokines, prostaglandins and nitric oxide in the regulation of stress-response systems.
Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis is accepted as one of the fundamental biological mechanisms that underlie major depression. This hyperactivity is caused by diminished feedback inhibition of...
Effects of catecholamines on blood pressure in the femoral bone marrow cavity in ovariectomized rats.
Menopausal women display changes in the osseous tissue (osteoporosis, pathologic fractures) and disorders in the function of cardiovascular system (hypertension, cardiovascular disease, arteriosclerosis, calcification)....
Age-related macular degeneration (AMD): pathogenesis and therapy.
Age-related macular degeneration (AMD) is a disease leading to severe visual loss and legal blindness in the elderly population. Its pathogenesis, likely multifactorial, involving a complex interaction of metabolic, func...
Effect of selected antidepressant drugs on cytochrome P450 2B (CYP2B) in rat liver. An in vitro and in vivo study.
The aim of the present study was to investigate the influence of antidepressants with different chemical structures and mechanisms of action affecting serotonergic and/or noradrenergic systems - tricyclic antidepressant...
Gender and the endothelium.
The understanding of the basis of gender differences in vascular function is of critical importance to establish gender targeted interventions in cardiovascular medicine. In this review we concentrate on the central role...