Yuusuke Hatanaka

Effect of estrogen on spine regulation in hippocampus

We have previously shown that emotional stimuli activate prolactinreleasing peptide (PrRP)-containing neurons in the brain. Here, we examined effects of PrRP administration upon anxiety-related behavior in rats. Wistar male rats were used. Animals were implanted with a guide cannula into the brain under avertin anesthesia. PrRP was injected into the lateral cerebral ventricle, or microinjected into the bed nucleus of the stria terminalis, dorsomedial hypothalamus, or hypothalamic paraventricular nucleus via the guide cannula. Fifteen minutes after the injection, rats were tested with an elevated plus maze test. Rats injected icv with PrRP or microinjected into the dorsomedial hypothalamus showed significantly reduced anxiety-related behavior. These data suggest that PrRP within the dorsomedial hypothalamus has anxiolytic effects in rats.