The effects of capsaicin on the neurosecretory cells of the paraventricular and supraoptic nucei in the adult rat / 대한해부학회지

ABSTRACT

Capsaicin, the pungent algesic substance of the red pepper is known to be a neurotoxic substance, interrupting the pain conducting pathway. To investigate the effects on the adult animals, immunohistochemical staining have been done after capsaicin treatment. Capsaicin 50 mg/kg was injected subcutaneously to the adult rats and after 1 week, 1 month and 2 months later, the morphometric change of vasopressin & oxytocin-secreting cells in supraoptic and paraventricular nuclei of the hypothalamic area were investigated. The count of vasopressin- and oxytocin-immunoreactive cells in supraoptic & paraventricular nuclei were decreasing from 1 month after capsaicin treatment and these decreasing was continued until 2 months. The area of neurons in the supraoptic & paraventricular nuclei were measured and they diminished in the all kinds of neurons. With the above results, capsaicin treatment in adult rats had no effects in central nervous system neurotransmitters, however, some part of the hypothalamus where blood brain barrier was not formed were affected. Therefore central nervous system could be affected by capsaicin depending upon the location.