To examine a role for the medullary nucleus paragigantocellularis ( @entity49933 ) in mediation of the symptomatology of opioid withdrawal, bilateral electrical stimulation of the @entity49933 was performed in conscious, unrestrained, opioid naive (nondependent) @entity35 . A characteristic series of behaviors was elicited during each 30-min session of @entity49933 stimulation. The profile of these behaviors resembled qualitatively, but was not quantitatively identical with those seen during precipitated withdrawal from @entity4784 . This @entity146 has been termed, opioid withdrawal-like behavior. The @entity146 were voltage-, but not frequency-, dependent. Tolerance to repeated stimulation of the @entity49933 did not develop following a series of 30-min runs of stimulation over 3.5 h. Intracerebroventricular (i.c.v.) injections of the nonselective opioid antagonist, @entity1510 , significantly decreased (by 40-50%) the intensity of stimulation-induced behavioral responses, as did injections of either the mu-selective ( @entity5541 , @entity5541 ) or the delta-selective ( @entity5172 , NTI) opioid antagonists. In contrast, similar i.c.v. injections of the kappa-selective antagonist, @entity14719 ( @entity14719 ), did not block behavioral responses to @entity49933 stimulation. The results indicate that activation of the @entity49933 by electrical stimulation can elicit behaviors similar to those observed during opioid withdrawal. Endogenous opioids, acting through mu- and delta-, but not kappa-opioid receptors, participate in mediating @entity146 induced by @entity49933 stimulation.

Electrical stimulation of nucleus paragigantocellularis induces @entity146 in the XXXX .

@entity5541 :: ('MESH:C024524', 'Chemical') :: ['beta-funaltrexamine', 'beta-FNA'] @entity35 :: ('10116', 'Species') :: ['rats'] @entity146 :: ('MESH:D001523', 'Disease') :: ['opioid withdrawal-like behaviors', 'behavioral syndrome'] @entity4784 :: ('MESH:D009293', 'Disease') :: ['opioid dependence'] @entity5172 :: ('MESH:C055382', 'Chemical') :: ['naltrindole'] @entity1510 :: ('MESH:D009270', 'Chemical') :: ['naloxone'] @entity14719 :: ('MESH:C051844', 'Chemical') :: ['nor-BNI', 'nor-binaltorphimine'] @entity49933 :: ('CHEBI:26345', 'Chemical') :: ['PGi']
@entity35 :: (10116,Species) :: ['rat']
