Sex-specific peptides from exocrine glands stimulate mouse vomeronasal sensory neurons

The discovery that sex hormones can be secreted from the eyes is something new in the world of sexual communication. A male-specific peptide secreted from the extraorbital lachrymal gland is transferred to the female's pheromone-sensing organ during physical contact such as facial grooming. It stimulates specific pheromone receptor neurons and elicits an electrical response. The ‘male’ peptide is a member of a previously unrecognized large multigene family of secreted peptides. A female signal, yet to be identified, acts in a similar way, suggesting that these pheromones operate via specific courtship behaviour to ensure sex recognition and discrimination.