Immediate prolactin release after pericommissural deafferentation in behaving male rats

Adult male rats received a chronic midline implant of Halász-type knife placed at the level of the anterior commissure. A chronically implanted heart cannula allowed for sequential blood sampling in unrestrained conditions. Anterior knife rotation of 180 degrees induced a significant increase of plasma prolactin concentration in 30 min. Plasma LH levels remained within control levels. It is suggested that neural projections dorsally entering the preoptic-suprachiasmatic region are significantly involved in the control of prolactin release in male rats.