Intracerebroventricular administration of anti-endothelin-1 IgG selectively upregulates endothelin-A and kappa opioid receptors.

Endothelin (ET) type A receptor antagonists enhance morphine-induced antinociception and restore morphine analgesia in morphine tolerant rats [Peptides 23 (2002) 1837; Peptides 24 (2003) 553]. These studies suggest that the central ET and opioid systems functionally interact. To explore this idea further, we determined the effect of i.c.v. administration of… (More)