Effect of melatonin on chronic bladder-ischaemia-associated changes in rat bladder function.

Area of Science:

• Urology
• Pharmacology
• Cardiovascular Research

Background:

• Oxidative stress contributes to bladder dysfunction.
• Chronic bladder ischemia, often linked to arterial occlusive disease, can cause functional and morphological changes.
• Melatonin possesses known antioxidant and free radical scavenging properties.

Purpose of the Study:

• To investigate the therapeutic potential of melatonin in a rat model of chronic ischemia-induced bladder dysfunction.
• To assess the impact of chronic melatonin treatment on bladder function and morphology under conditions of oxidative stress.

Main Methods:

• Adult male Sprague-Dawley rats were subjected to arterial injury and a high-cholesterol diet to induce chronic bladder ischemia and oxidative stress.
• Rats received either low-dose (2.5 mg/kg/day) or high-dose (20 mg/kg/day) melatonin orally for 8 weeks.
• Urodynamic investigations, pharmacological studies, and histological/immunohistochemical analyses of bladder and iliac artery tissues were performed.

Main Results:

• Arterial injury led to bladder hyperactivity, reduced bladder capacity, and impaired contractile responses, accompanied by increased collagen, oxidative stress, and inducible nitric oxide synthase (NOS) expression.
• High-dose melatonin treatment significantly improved bladder function and morphology, reduced oxidative stress, and normalized NOS expression compared to the arterial injury group.
• Low-dose melatonin showed some beneficial effects, but they did not reach statistical significance.

Conclusions:

• Chronic bladder ischemia induces oxidative stress and bladder hyperactivity.
• Chronic high-dose melatonin treatment demonstrates significant protective effects on bladder function and morphology in this model.
• Melatonin's antioxidant properties likely mediate its benefits, suggesting its potential as a therapeutic agent for ischemia-related bladder dysfunction.