title: Disproportionate loss of CA4 parvalbumin-immunoreactive interneurons in patients with Ammon's horn sclerosis.
abstract: We studied differences in the number and morphology of parvalbumin-immunoreactive (PV-IR) interneurons in 43 hippocampal specimens from patients with classical Ammon's horn sclerosis (AHS) who underwent anterior temporal lobectomy, as compared with 14 autopsy and non-AHS surgical control specimens. PV-IR neuronal loss in the AHS specimens varied significantly from that expected based on overall AHS-associated pyramidal and granule neuron loss. Most striking was the loss of PV-IR interneurons in CA4 of the AHS specimens, which was 12 times greater than AHS-associated pyramidal neuron loss, and significantly exceeded the PV-IR interneuron loss observed in the other sectors of the hippocampus. In addition, the PV-IR interneurons in the AHS specimens had markedly smaller and less defined cell bodies and shortened and simplified dendritic arbors compared with the PV-IR interneurons in the control specimens. Other differences noted in the AHS specimens included prominent dendritic varicosities; the loss or interruption of a band formed by PV-IR terminals in the dentate gyrus; and the virtual absence of a small, intensely staining PV-IR interneuron with a short, exuberant dendritic arbor that was readily identified in the autopsy specimens. We discuss these findings in relationship to the development of classical AHS and complex partial seizures (CPS).
authors.affiliation: Department of Neurosurgery, Baylor College of Medicine, Houston, Texas 77030, USA.
authors.forename: Z Q
authors.initials: ZQ
authors.lastname: Zhu
authors.forename: D L
authors.initials: DL
authors.lastname: Armstrong
authors.forename: W J
authors.initials: WJ
authors.lastname: Hamilton
authors.forename: R G
authors.initials: RG
authors.lastname: Grossman
mesh_terms: D000293:Adolescent; D000328:Adult; D002452:Cell Count; D017029:Epilepsy, Complex Partial / Q000378:metabolism* / Q000473:pathology*; D005260:Female; D006624:Hippocampus / Q000378:metabolism* / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D007395:Interneurons / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D010320:Parvalbumins / Q000378:metabolism*; D017966:Pyramidal Cells / Q000473:pathology; D012598:Sclerosis
chemical_list: D010320:Parvalbumins