in an attempt to determine the physiological role of these receptor systems , experiments were carried out in which the plasma acth and serum corticosterone concentrations were determined before and after stress in rats treated s.c. with selective antagonists of mu- ( naloxone , naltrexone ) , delta- ( ici 174864 ) and kappa- ( mr2266 ) opioid receptors .
C0027358
naloxone
C0027360
naltrexone