Effects of sustained gamma-hydroxybutyrate treatments on spontaneous and evoked firing activity of locus coeruleus norepinephrine neurons.

Journal Article

BACKGROUND: Gamma-hydroxybutyrate is currently used to promote nighttime sleep in the treatment of narcolepsy; however, it is also a drug of abuse ("Liquid Ecstasy") associated with a withdrawal syndrome with anxiety features. Of interest, the activity of locus coeruleus neurons is a reflective index of these above mentioned behavioral states. METHODS: Using in vivo extracellular unitary recordings, sustained administration of gamma-hydroxybutyrate (40 mg/kg/day via minipump implanted subcutaneously) on the spontaneous and sensory-evoked burst firing of locus coeruleus norepinephrine neurons was assessed in rats. RESULTS: A 2-day and 10-day gamma-hydroxybutyrate administration decreased the spontaneous firing activity of locus coeruleus neurons by 52% and 54%, respectively, when compared with controls. A similar degree of attenuation on evoked burst firing of norepinephrine neurons also occurred in these rats (2-day gamma-hydroxybutyrate: 47% and 10-day gamma-hydroxybutyrate: 58%), when compared with controls. In contrast, rats treated with gamma-hydroxybutyrate for 10 days followed by removal of the minipump for 36 hours resulted in a 33% augmentation in spontaneous locus coeruleus activity as compared with controls. Furthermore, a robust 79% increase in burst firing in response to paw-pinch was exhibited in theses rats. CONCLUSIONS: Chronic gamma-hydroxybutyrate treatment inhibits the spontaneous and sensory-evoked burst firing of locus coeruleus norepinephrine neurons, whereas these indices are enhanced during drug withdrawal. The alteration in norepinephrine activity during chronic gamma-hydroxybutyrate administration may contribute to the ability of this agent to induce sleep and regulate narcoleptic episodes. Enhanced norepinephrine activity during withdrawal may be related to symptoms of anxiety on rapid termination of this drug in abusers.

Full Text

Duke Authors

Cited Authors

  • Szabo, ST; Gold, MS; Goldberger, BA; Blier, P

Published Date

  • May 2004

Published In

Volume / Issue

  • 55 / 9

Start / End Page

  • 934 - 939

PubMed ID

  • 15110737

Electronic International Standard Serial Number (EISSN)

  • 1873-2402

International Standard Serial Number (ISSN)

  • 0006-3223

Digital Object Identifier (DOI)

  • 10.1016/j.biopsych.2003.12.013

Language

  • eng