“The κ opioid agonists U-62,066E and (−) ethylketocyclazocine , but not the μ agonist [D-Ala2,N-MePhe4,Gly5-ol]-enkephalin (DAGO) nor the δ agonist [D-Pen2,5]enkephalin (DPDE), inhibited the potassium-evoked release of L-glutamate and dynorphin B-like immunoreactivity.”