PRLR and Anxiety: 2009; Torner et al. 2001). Downregulation of brain prolactin receptors increased anxiety-related behavior demonstrating an anxiolytic effect of PRL acting at brain level (Torner et al. 2001). Furthermore stress-induced increase of corticotropin secretion was decreased after chronic intracerebroventricular infusion of PRL (Torner et al. 2001). Fujikawa (2004) showed that PRL levels increase in response to stress acting on the central nervous system and plays an important role in helping to protect against acute stress-induced hypocalcemia.