Quantitative histological changes in the hypothalamic nuclei in the prepuberal, puberal and postpuberal female rat

Summary The nuclear sizes of the nerve cells in the various hypothalamic nuclei have been studied in the prepuberal, puberal and postpuberal female rat. The nuclear sizes of the anterior hypothalamic nucleus, dorsomedial nucleus and medial part of the ventro-medial nucleus did not show any significant changes during each period. In the supra-optic nucleus and paraventricular nucleus, the characteristics increases of the nuclear size was observed at the onset of puberty. However, no difference was observed after the onset of the puberty. In the suprachiasmatic nucleus, postterior of the ventromedial nucleus and arcuate nucleus, the significant increase of the nuclear size was observed between the day of vaginal opening and the 70th day, but there was no difference between 70-day-old and 100-day-old animals.