title: Alterations of GABA(A)beta2/3 immunoreactivity in the dentate gyrus after perforant pathway lesion.
abstract: Immunocytochemical techniques were employed to examine the changes in the GABA receptor subunits beta2/3 within the dentate gyrus of the rat brain 1, 3, 7, 14, 30 and 90 days after a unilateral perforant pathway lesion. Three days post-lesion we observed a decrease in beta2/3 immunolabeling in the inner molecular layer of the dentate gyrus followed by a comparable decrease in the outer molecular layer 7 days post-lesion. These decreases were transient; 30 and 90 days post-lesion, beta2/3 immunolabeling appeared similar to controls in the inner portion of the molecular layer, while in the outer region the labeling was increased. In this latter region we also observed a dense band of AChE fibers. Following survival times of 3 days we observed a diffuse staining of the neuropil in the hilar region, and a dense amorphous accumulation of peroxidase reaction product in the polymorphic region. These responses were transient and by 14 days the hilar/polymorphic region appeared indistinguishable from controls. These data suggest a unique pattern of immunoabeling in the molecular and polymorphic region in response to perforant pathway lesion. A putative explanation for this response is discussed.
authors.affiliation: Neuroscience Research Center, MPC Hahnemann School of Medicine, Allegheny-Campus, Pittsburgh, PA 15212, USA.
authors.forename: K
authors.initials: K
authors.lastname: Mizukami
authors.forename: M D
authors.initials: MD
authors.lastname: Ikonomovic
authors.forename: A
authors.initials: A
authors.lastname: Mishizen
authors.forename: R
authors.initials: R
authors.lastname: Sheffield
authors.forename: D R
authors.initials: DR
authors.lastname: Grayson
authors.forename: D M
authors.initials: DM
authors.lastname: Armstrong
authors.forename: A
authors.initials: A
authors.lastname: Mishizin
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D018891:Dentate Gyrus / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D009412:Nerve Fibers / Q000201:enzymology; D019581:Neuropil / Q000166:cytology / Q000201:enzymology; D019580:Perforant Pathway / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011963:Receptors, GABA-A / Q000378:metabolism*
chemical_list: D011963:Receptors, GABA-A; D000110:Acetylcholinesterase