The prolactin releasing peptides: RF-amide peptides

Although dopamine is considered the major hypothalamic controller of prolac tin release from the anterior pituitary gland. there is evidence that a yet to be discovered prolactin releasing factor (PRF) also exists in brain. Re cently, two peptides were isolated, products of the same prohormone, that w ere reported to have significant prolactin-re leasing activity. These pepti des, called prolactin releasing peptides, are not accepted by all investiga tors to be in fact PRF's. Instead, it appears that their widespread distrib ution in brain and the presence of receptors for the peptides in sites unre lated to neuroendocrine function are the basis for a variety of central ner vous system action including activation of the autonomic nervous system. Th us, these peptides may not be PRFs, but instead neuroactive agents that are involved in many brain circuits with divergent functions.