RT Journal Article
SR Electronic
T1 Corticotropin Releasing Hormone Type 2 Receptors in the Dorsal Raphe Nucleus Mediate the Behavioral Consequences of Uncontrollable Stress
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 1019
OP 1025
DO 10.1523/JNEUROSCI.23-03-01019.2003
VO 23
IS 3
A1 Sayamwong E. Hammack
A1 Megan J. Schmid
A1 Matthew L. LoPresti
A1 Andre Der-Avakian
A1 Mary Ann Pellymounter
A1 Alan C. Foster
A1 Linda R. Watkins
A1 Steven F. Maier
YR 2003
UL http://www.jneurosci.org/content/23/3/1019.abstract
AB Uncontrollable shock produces a constellation of behavioral changes that are not observed after equivalent escapable shock. These include interference with escape and potentiation of fear conditioning. The activation of corticotropin-releasing hormone (CRH) receptors within the caudal dorsal raphe nucleus (DRN) during inescapable tailshock (IS) has been shown to be critical for the development of these behavioral changes. CRH binds to two receptor subtypes, both of which are found in the DRN. The present set of studies examined which CRH receptor subtype mediates the effects of IS. Intra-DRN administration of the CRH2 receptor antagonist anti-sauvagine-30 before IS dose-dependently blocked IS-induced behavioral changes; the CRH1 receptor antagonist 2-methyl-4-(N-propyl-N-cycloproanemethylamino)-5-chloro-6-(2,4,6-trichloranilino)pyrimidine (NBI27914), administered in the same manner, did not. Moreover, the highly selective CRH2 receptor agonist urocortin II (Ucn II) dose-dependently caused behavioral changes associated with IS in the absence of shock. Ucn II was effective at doses 100-fold lower than those previously required for CRH. The relationship between CRH2 receptors and DRN 5-HT is discussed.