Changes in GABAergic and non-GABAergic synapses during chronic ethanol exposure and withdrawal in the dentate fascia of LS and SS mice.
Ethanol-sensitive LSIBG and ethanol-insensitive SSIBG mice were exposed to ethanol (23.5% ethanol-derived calories) for 4 months. Half of the animals was sacrificed at this time and the other half was withdrawn from the ethanol diet for 1 month. GABA immunoelectron microscopy was used to study the impact of the treatments on synaptic contacts in the dentate molecular layer. In the LS mice a significant loss of non-GABAergic axospinous synapses (26.7%; p < 0.05) was observed during ethanol exposure which was followed by a loss of GABAergic synapses on dendritic shafts (54.7%; p < 0.01) during withdrawal. In the SS mice there was a significant decrease in the non-GABAergic axospinous synapses (23.5%; p < 0.05) and a significant increase in axodendritic synapses (63.3%; p < 0.05) during ethanol exposure. The observed changes in the GABAergic and non-GABAergic innervation of the dentate fascia induced by ethanol were observed in the projection zone of the perforant path. They could adversely affect the hippocampal physiology with a consequent impairment of mnemonic functions.
Department of Psychology, University of Colorado, Boulder 80309.
E
E
Fifková
H
H
Eason
K
K
Bueltmann
J
J
Lanman
D000430:Alcohol Withdrawal Delirium / Q000473:pathology*; D000437:Alcoholism / Q000473:pathology*; D000818:Animals; D001369:Axons / Q000187:drug effects / Q000473:pathology; D003712:Dendrites / Q000187:drug effects / Q000473:pathology; D000431:Ethanol / Q000493:pharmacokinetics / Q000633:toxicity; D006624:Hippocampus / Q000187:drug effects / Q000473:pathology*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D016253:Microscopy, Immunoelectron; D018079:Receptors, GABA / Q000502:physiology*; D013569:Synapses / Q000187:drug effects / Q000473:pathology*; D005680:gamma-Aminobutyric Acid / Q000502:physiology*
D018079:Receptors, GABA; D000431:Ethanol; D005680:gamma-Aminobutyric Acid