30 years after: CNS actions of prolactin: Sources, mechanisms and physiological significance.

Our understanding of the neural actions of prolactin (PRL) and its biochemical basis has expanded greatly over the past three decades. During this time, major progress has been made, including clarification of how PRL accesses the brain, identification of the PRL receptor and the sites where it is expressed within the brain, determination of the neurochemical mechanism of action of PRL and its effect on genomic expression in neurones, identification of the neural sites where PRL acts to stimulate maternal behaviour and related affective states, and exploration of how life experiences impact neural PRL receptor activity and actions. The next 30 years promise to reveal a myriad of basic and clinical findings regarding new roles for PRL and a greater indepth understanding of how and where PRL affects physiological and behavioural processes.