Disproportionate loss of CA4 parvalbumin-immunoreactive interneurons in patients with Ammon's horn sclerosis.
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).
Zhu
Z Q
ZQ
Department of Neurosurgery, Baylor College of Medicine, Houston, Texas 77030, USA.
Armstrong
D L
DL
Hamilton
W J
WJ
Grossman
R G
RG
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
D010320:Parvalbumins