Intracerebroventricular injection of anti-prolactin serum suppresses excessive grooming of pituitary homografted rats.

Rats with endogenous hyperprolactinaemia, as induced by pituitary homografts under the kidney capsule, displayed increased grooming behavior as compared to that of sham-operated animals. Twelve days after surgery, intracerebroventricular injection of anti-prolactin serum (dilution 1:100, 1 microliter) suppressed the excessive grooming of homografted rats. These observations suggest that prolactin from a peripheral source may reach the central nervous system to affect brain mechanisms involved in grooming behavior.