Organization of cortico-cortical associative projections in a rat model of microgyria.
Microgyria was experimentally induced by focal freezing lesions of the frontal cortex in newborn rats. Adult microgyric animals received cortical injections of biotinylated dextran amine combined with NMDA, in order to obtain a Golgi-like retrograde labeling of cortico-cortical association neurons. Injections were performed either rostrally or caudally to the microgyric lesion. Results demonstrate that long-range association projections traveling across the zone of the microgyric lesion arise mainly from infragranular layers. In normal animals the same projections originate both from supragranular and infragranular layers. The analysis of single basal dendrites of layer 2/3 in microgyric animals demonstrates a simplified branching pattern, with a number of end points lower than in control animals. Potential implications for microgyria-associated epilepsy are discussed.
Institute of Anatomy, Catholic University Medical School, Rome, Italy.
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S
Giannetti
P
P
Gaglini
F
F
Di Rocco
C
C
Di Rocco
A
A
Granato
D000818:Animals; D000831:Animals, Newborn; D001370:Axonal Transport; D001710:Biotin / Q000031:analogs & derivatives*; D001921:Brain / Q000002:abnormalities*; D002540:Cerebral Cortex / Q000002:abnormalities*; D003911:Dextrans; D004195:Disease Models, Animal; D005456:Fluorescent Dyes; D005625:Frontal Lobe / Q000293:injuries / Q000473:pathology; D016202:N-Methylaspartate / Q000493:pharmacokinetics; D009434:Neural Pathways / Q000166:cytology / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar
D003911:Dextrans; D005456:Fluorescent Dyes; C076397:biotinylated dextran amine; D016202:N-Methylaspartate; D001710:Biotin