Arginine vasotocin (AVT), an alleged hormone of the mammalian pineal gland.

Arginine vasotocin has been proposed as a hormone of the mammalian pineal gland. This claim is largely based on biological and immunological results, although some chemical evidence has also been provided. Yet, more and more researchers have recently disclaimed the presence of this nonapeptide in mammalian tissue. The currently available evidence is critically reviewed exposing the dispute as a real one urgently requiring final settlement.