The thalamo-cortico-thalamic loop was investigated in adult rats exposed to ethanol during the last week of fetal life. Animals underwent either cortical or thalamic injections of lectin-conjugated horseradish peroxidase. Results demonstrate that prenatal exposure to ethanol causes permanent changes in the thalamocortical circuits. Alterations of thalamo-cortical and cortico-thalamic projections are concentrated at the level of axon terminal fields. The most severe thalamic damage is observed in the anterior intralaminar and midline nuclei; crossed cortico-thalamic projections also appear to be severely impaired. In the cortex, the damage to thalamic terminals displays a medio-lateral gradient of increasing severity through sensori-motor areas, with the lateral fields more impaired. Cells of origin of thalamo-cortical and cortico-thalamic projections are less affected by prenatal ethanol exposure: in the thalamus and layer 5 of sensori-motor cortex labeled cells exhibit normal values of areal numeric density. Conversely, cortico-thalamic neurons of layer 6, especially in the lateral agranular sensori-motor field, display smaller values of areal density than those of normal animals. Possible mechanisms underlying the establishment of these abnormalities are discussed.
Multifaceted alterations of the thalamo-cortico-thalamic loop in adult rats prenatally exposed to ethanol / GRANATO A; D. MINCIACCHI; SANTARELLI M; SBRICCOLI A. - In: ANATOMY AND EMBRYOLOGY. - ISSN 0340-2061. - STAMPA. - 191:(1995), pp. 11-23.
Multifaceted alterations of the thalamo-cortico-thalamic loop in adult rats prenatally exposed to ethanol.
MINCIACCHI, DIEGO;
1995
Abstract
The thalamo-cortico-thalamic loop was investigated in adult rats exposed to ethanol during the last week of fetal life. Animals underwent either cortical or thalamic injections of lectin-conjugated horseradish peroxidase. Results demonstrate that prenatal exposure to ethanol causes permanent changes in the thalamocortical circuits. Alterations of thalamo-cortical and cortico-thalamic projections are concentrated at the level of axon terminal fields. The most severe thalamic damage is observed in the anterior intralaminar and midline nuclei; crossed cortico-thalamic projections also appear to be severely impaired. In the cortex, the damage to thalamic terminals displays a medio-lateral gradient of increasing severity through sensori-motor areas, with the lateral fields more impaired. Cells of origin of thalamo-cortical and cortico-thalamic projections are less affected by prenatal ethanol exposure: in the thalamus and layer 5 of sensori-motor cortex labeled cells exhibit normal values of areal numeric density. Conversely, cortico-thalamic neurons of layer 6, especially in the lateral agranular sensori-motor field, display smaller values of areal density than those of normal animals. Possible mechanisms underlying the establishment of these abnormalities are discussed.I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.