PMID- 12455007
OWN - NLM
STAT- MEDLINE
DCOM- 20030122
LR  - 20181113
IS  - 0021-9967 (Print)
IS  - 1096-9861 (Electronic)
IS  - 0021-9967 (Linking)
VI  - 454
IP  - 4
DP  - 2002 Dec 23
TI  - Structural and functional asymmetry in the normal and epileptic rat dentate 
      gyrus.
PG  - 424-39
AB  - The rat dentate gyrus is usually described as relatively homogeneous. Here, we 
      present anatomic and physiological data which demonstrate that there are striking 
      differences between the supra- and infrapyramidal blades after status epilepticus 
      and recurrent seizures. These differences appear to be an accentuation of a 
      subtle asymmetry present in normal rats. In both pilocarpine and kainic acid 
      models, there was greater mossy fiber sprouting in the infrapyramidal blade. This 
      occurred primarily in the middle third of the hippocampus. Asymmetric sprouting 
      was evident both with Timm stain as well as antisera to brain-derived 
      neurotrophic factor (BDNF) or neuropeptide Y (NPY). In addition, surviving 
      NPY-immunoreactive hilar neurons were distributed preferentially in the 
      suprapyramidal region of the hilus. Extracellular recordings from infrapyramidal 
      sites in hippocampal slices of pilocarpine-treated rats showed larger population 
      spikes and weaker paired-pulse inhibition in response to perforant path 
      stimulation relative to suprapyramidal recordings. A single stimulus could evoke 
      burst discharges in infrapyramidal granule cells but not suprapyramidal blade 
      neurons. BDNF exposure led to spontaneous epileptiform discharges that were 
      larger in amplitude and longer lasting in the infrapyramidal blade. Stimulation 
      of the infrapyramidal molecular layer evoked larger responses in area CA3 than 
      suprapyramidal stimulation. In slices from the temporal pole, in which anatomic 
      evidence of asymmetry waned, there was little evidence of physiological asymmetry 
      either. Of interest, some normal rats also showed signs of greater evoked 
      responses in the infrapyramidal blade, and this could be detected with both 
      microelectrode recording and optical imaging techniques. Although there were no 
      signs of hyperexcitability in normal rats, the data suggest that there is some 
      asymmetry in the normal dentate gyrus and this asymmetry is enhanced by seizures. 
      Taken together, the results suggest that supra- and infrapyramidal blades of the 
      dentate gyrus could have different circuit functions and that the infrapyramidal 
      blade may play a greater role in activating the hippocampus.
CI  - Copyright 2002 Wiley-Liss, Inc.
FAU - Scharfman, Helen E
AU  - Scharfman HE
AD  - Center for Neural Recovery and Rehabilitation Research, Helen Hayes Hospital, 
      West Haverstraw, New York 10993-1195, USA. scharfmanh@helenhayeshosp.org
FAU - Sollas, Anne L
AU  - Sollas AL
FAU - Smith, Karen L
AU  - Smith KL
FAU - Jackson, Meyer B
AU  - Jackson MB
FAU - Goodman, Jeffrey H
AU  - Goodman JH
LA  - eng
GR  - NS38285/NS/NINDS NIH HHS/United States
GR  - R56 NS037562/NS/NINDS NIH HHS/United States
GR  - R01 NS037562-04/NS/NINDS NIH HHS/United States
GR  - R01 NS037562/NS/NINDS NIH HHS/United States
GR  - NS37212/NS/NINDS NIH HHS/United States
GR  - NS37562/NS/NINDS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - J Comp Neurol
JT  - The Journal of comparative neurology
JID - 0406041
RN  - 0 (Brain-Derived Neurotrophic Factor)
RN  - 0 (Excitatory Amino Acid Agonists)
RN  - 0 (Muscarinic Agonists)
RN  - 0 (Neuropeptide Y)
RN  - 01MI4Q9DI3 (Pilocarpine)
RN  - SIV03811UC (Kainic Acid)
SB  - IM
MH  - Animals
MH  - Brain-Derived Neurotrophic Factor/analysis
MH  - Dentate Gyrus/*anatomy & histology/pathology/*physiology/physiopathology
MH  - Electrophysiology
MH  - Excitatory Amino Acid Agonists
MH  - Immunohistochemistry
MH  - Kainic Acid
MH  - Male
MH  - Mossy Fibers, Hippocampal/anatomy & 
      histology/pathology/physiology/physiopathology
MH  - Muscarinic Agonists
MH  - Neuropeptide Y/analysis
MH  - Pilocarpine
MH  - *Rats
MH  - Rats, Sprague-Dawley
MH  - Seizures/pathology/physiopathology
MH  - Status Epilepticus/chemically induced/*pathology/*physiopathology
MH  - Synapses/pathology/physiology
PMC - PMC2519114
MID - NIHMS59824
EDAT- 2002/11/28 04:00
MHDA- 2003/01/23 04:00
PMCR- 2008/08/23
CRDT- 2002/11/28 04:00
PHST- 2002/11/28 04:00 [pubmed]
PHST- 2003/01/23 04:00 [medline]
PHST- 2002/11/28 04:00 [entrez]
PHST- 2008/08/23 00:00 [pmc-release]
AID - 10.1002/cne.10449 [doi]
PST - ppublish
SO  - J Comp Neurol. 2002 Dec 23;454(4):424-39. doi: 10.1002/cne.10449.