抄録
The critical function of Oxytocin and Oxytocin Receptor was well known to stimulate uterine contraction in parturition and eject milk for feeding pups. Recent publications also showed the critical role of Oxytocin Receptor (OXTR) expressed in brain on regulation of wide-spectrally physiological and behavioral functions. Our study using mice defect in ligand Oxytocin and its Receptor (Oxytocin Receptor) genes showed essential roles of them on suppression of the aggressiveness of male mice to be the level as well as that of the WT animals. In contrast, although OXTR-/- female mice displayed impaired nurturing behavior, including pups retrieving and crouching over behaviors, OXT-/- female mice, even born form breeding pairs of the null parents did not. To further study in details about the physiological function of neurons expressing OXTR and to obtain clue to explain these discrepancy in mechanism establishing male and female social behaviors, we newly generated OXTR-Venus knockin mice. It could contribute to clearly locate the OXTR expressing neurons (OXTR neurons) in even live brain slice of the mice. We will also show a preliminary data about the discrepancy in distribution of the neurons expressing OXTR at PVN and SON of the hypothalamus in males and in milk feeding females. [J Physiol Sci. 2008;58 Suppl:S41]
