Effects of melatonin supplementary on the sciatic nerve conduction velocity in the ovariectomized-aged rat.

Objectives: Melatonin is a potent antioxidant agent and an anti-aging hormone. Serum melatonin level declines during the menopause. Estradiol, a neuroprotective ovarian hormone, also decreases during the menopause. The purpose of this study is to evaluate the effect of melatonin supplementary on peripheral nerve function in the ovariectomized (OVX)-aged rats.

Methods: Randomly selected OVX-aged Wistar rats received injections of melatonin (5 or 20 mg/kg) daily either two or six weeks. Nerve conduction velocities and distal latencies were determined from the propagation of action potential recorded by using an extracellular electrophysiological technique.

Results: The mean distal latencies of melatonin-treated groups were shorter than that of the control group. Thus, the nerve conduction velocity was significantly greater in both two weeks and six weeks melatonin treated groups as compared to the controls (p<0.001).

Conclusion: Melatonin alleviates the electrophysiological properties of the sciatic nerve in OVX-aged rats. Thus, melatonin supplementary may have a potential clinical application for the treatment of postmenopausal peripheral nerve degeneration.