Stimulation of hypothalamic beta-endorphin and dynorphin release by corticotropin-releasing factor (in vitro)

Corticotropin-releasing factor (CRF) at doses of 10(-12)-10(-8) M significantly stimulated the release of beta-endorphin and dynorphin from superfused rat hypothalamic slices. These effects were shown to be mediated by the CRF receptor since they were antagonized by the CRF receptor antagonist alpha-helical CRF9-41 (10(-6) M). The two opioid peptides showed different time courses of response and in the case of beta-endorphin, an attenuation of the response upon continued exposure to CRF was observed.