Prolonged foot-shock induced analgesia: glucocorticoids and non-pituitary opioids are involved.
In rats, the analgesic response induced by prolonged intermittent foot-shock is abolished by naloxone or adrenalectomy, and is restored in adrenalectomized animals by the administration of dexamethasone or corticosterone, but not deoxycorticosterone. Levels of immunoreactive beta-endorphin in the anterior pituitary are significantly elevated by adrenalectomy alone, and further by dexamethasone and corticosterone; in contrast, immunoreactive beta-endorphin levels in the neuro-intermediate lobe are raised by deoxycorticosterone. These findings suggest that analgesic responses produced by prolonged intermittent foot-shock involve both the pituitary-adrenal axis and endogenous, non-pituitary opioids.
D000315:Adrenalectomy; D000698:Analgesia; D000818:Animals; D003345:Corticosterone / Q000494:pharmacology*; D003900:Desoxycorticosterone / Q000494:pharmacology*; D003907:Dexamethasone / Q000494:pharmacology*; D004597:Electroshock; D004723:Endorphins / Q000032:analysis*; D005260:Female; D009020:Morphine / Q000494:pharmacology*; D009270:Naloxone / Q000494:pharmacology*; D010903:Pituitary Gland, Anterior / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D001615:beta-Endorphin
D004723:Endorphins; D009270:Naloxone; D003900:Desoxycorticosterone; D001615:beta-Endorphin; D009020:Morphine; D003907:Dexamethasone; D003345:Corticosterone