Melatonin affects red deer spermatozoa motility and physiology in capacitating and non-capacitating conditions.

Melatonin affects sperm physiology, possibly through membrane receptors. Effects were tested at low concentrations (1 pM, 100 pM, 10 nM and 1 µM) in red deer epididymal spermatozoa as a model for high-seasonality species. Samples were incubated with melatonin as uncapacitated or capacitating conditions (heparin) and evaluated for motility and physiology (flow cytometry).