Linked Life Data

7583249

Source:http://linkedlifedata.com/resource/pubmed/id/7583249

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
1995-11-30
pubmed:abstractText
Previous studies from our laboratory showed that ethanol enhances muscarinic excitatory responses in rat hippocampal neurons in vivo and, like muscarinic agonists, reduces the M-current (IM) in these neurons in vitro. Therefore, we used extracellular and intracellular recording techniques in the hippocampal slice preparation to examine the mechanisms underlying this ethanol-muscarinic interaction. Surprisingly, superfusion or local application of low concentrations of acetylcholine (ACh), carbachol (CCh) or muscarine reduced the amplitudes of CA1 field potentials evoked by stratum radiatum (SR) stimulation. This effect was blocked by 1 microM atropine but was independent of the method of agonist application, the site of application or the SR stimulus paradigm. In intracellular and extracellular single unit recordings, cholinergic depressions of field potentials were correlated with: (1) depolarization of pyramidal neurons; (2) spike discharge increases; (3) reduction of amplitudes of postsynaptic potentials and (4) reduction of late afterhyperpolarizations (AHPs). Superfusion of low ethanol concentrations (11-22 mM) alone had little effect on SR-evoked field potentials but enhanced (by 10-90%) both the depressions of evoked field potentials and depolarizations elicited by the muscarinic agonists. Ethanol (22-44 mM) also enhanced both the amplitude and duration of the muscarinic slow excitatory postsynaptic potentials (sEPSPs) recorded intracellularly in CA1 and CA3 neurons. This effect was enhanced by eserine and blocked by atropine, verifying involvement of muscarinic receptors. These results suggest that: (1) caution be used in interpreting results of field potential studies regarding drug-induced excitability changes; and (2) ethanol in just-intoxicating concentrations enhances endogenous muscarinic synaptic transmission as well as responses to exogenous muscarinic agonists.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-8993
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
685
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
21-32
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Ethanol enhances muscarinic cholinergic neurotransmission in rat hippocampus in vitro.
pubmed:affiliation
Alcohol Research Center, Scripps Research Institute, La Jolla, CA 92037, USA.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.