Differential sensitivity of hippocampal interneurons to ethanol in adolescent and adult rats.

Published

Journal Article

Ethanol (EtOH) promotes GABAergic synaptic transmission in the central nervous system. We have shown that EtOH enhances the frequency of GABA(A) receptor-mediated spontaneous inhibitory postsynaptic currents less powerfully in hippocampal CA1 pyramidal neurons from adolescent animals compared with those from adults. However, we have also shown that EtOH promotes the firing of hippocampal interneurons, located in stratum lacunosum moleculare (SLM), from adolescent animals more potently than in those from adults. Thus the latter finding would seem to be inconsistent with the former. To understand this apparent inconsistency, we have now assessed the effects of EtOH on a different subpopulation of hippocampal interneurons, those with somata located in the stratum oriens (SO). We found that EtOH-induced enhancement of the frequency of spontaneous action potentials (sAPs) was less in interneurons from adolescent rats compared with those from adults. In addition, EtOH-induced reduction of the afterhyperpolarization decay time constant (τ(slow)) was less pronounced in interneurons from adolescent rats, as was the EtOH-induced increase in the amplitude of the hyperpolarization-activated cation current, I(h). The effect of EtOH on sAP firing frequency was blocked by application of the I(h) antagonist 4-ethylphenylamino-1,2-dimethyl-6-methylaminopyrimidinium chloride (ZD7288). These results indicate that although EtOH promotes the firing of hippocampal interneurons, through promotion of I(h), the developmental expression of this effect differs between interneurons with somata located in the SO and SLM.

Full Text

Duke Authors

Cited Authors

  • Yan, H; Li, Q; Madison, R; Wilson, WA; Swartzwelder, HS

Published Date

  • October 2010

Published In

Volume / Issue

  • 335 / 1

Start / End Page

  • 51 - 60

PubMed ID

  • 20660126

Pubmed Central ID

  • 20660126

Electronic International Standard Serial Number (EISSN)

  • 1521-0103

Digital Object Identifier (DOI)

  • 10.1124/jpet.110.168450

Language

  • eng

Conference Location

  • United States