The neuroprotective activities of melatonin against the Alzheimer beta-protein are not mediated by melatonin membrane receptors.
Pappolla MA, Simovich MJ, Bryant-Thomas T, Chyan YJ, Poeggeler B, Dubocovich M, Bick R, Perry G, Cruz-Sanchez F, Smith MA. The neuroprotective activities of melatonin against the Alzheimer beta-protein are not mediated by melatonin membrane receptors. J Pineal Res. 2002 Apr; 32(3):135-42.