Veni, vidi, vici: the neurohypophysis in the twentieth century

We outline the key discoveries in the first 70 years of research on the neurohypophysis that provided the foundations for more recent studies in the last 30 years. We consider the extent to which these recent studies, which have exploited molecular technologies, cellular electrophysiological techniques and mechanistic behavioural investigations, have advanced or changed our understanding of the functions of oxytocin and vasopressin. The different evolutionary pressures on the oxytocin and vasopressin systems are discussed. Lastly, we focus on the mechanisms underlying the burst-firing activity of oxytocin neurones in lactation as a problem not yet solved, and probably requiring a presently improbable conceptual leap to understand.