Synaptic reorganisation of the mediodorsal thalamic nucleus in adult rat following chronic prefrontal cortical lesions.
Chronic changes in the thalamic mediodorsal nucleus (MD) after unilateral lesions of the prefrontal cortex were studied with the aid of quantitative light, and electron microscopic immunohistochemistry. Three months after the lesions, although the size of MD ipsilateral to the lesion did not change considerably, the neuronal density was significantly reduced. Conversely, as demonstrated by quantitative electron microscopy, the density of GABA immunostained axon terminals significantly increased in the lesioned side. It is suggested, that as MD does not contain GABA cells, the reactive hyperinnervation of the MD by GABA-containing axons is of extrinsic origin. This finding is also the morphological evidence of the potential of GABA-ergic nerve cells for reactive (induced) axonal sprouting.
Négyessy
L
L
1st Department of Anatomy, Semmelweis Medical University, Budapest, Hungary.
Takács
J
J
Mogensen
J
J
Divac
I
I
Hámori
J
J
D000818:Animals; D001369:Axons / Q000502:physiology / Q000648:ultrastructure; D007839:Functional Laterality; D007150:Immunohistochemistry; D008297:Male; D016253:Microscopy, Immunoelectron; D009474:Neurons / Q000166:cytology* / Q000648:ultrastructure; D017397:Prefrontal Cortex / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012016:Reference Values; D013569:Synapses / Q000502:physiology / Q000648:ultrastructure*; D013787:Thalamic Nuclei / Q000166:cytology* / Q000648:ultrastructure; D005680:gamma-Aminobutyric Acid / Q000032:analysis*
D005680:gamma-Aminobutyric Acid