European Journal of Anatomy

Official Journal of The Spanish Society of Anatomy
/> Cover Volume 10 - Number 3
Eur J Anat, 10 (3): 127-142 (2006)

Interaction between ?-amyloid protein and the ?7 nicotinic acetylcholine receptor in cholinergic, gabaergic and calcium-binding proteins-containing neurons in the septum-diagonal band complex of the rat

Gonzalo-Ruiz A., Arevalo-Serrano J.

Laboratory of Neuroanatomy, Institute of Neuroscience of Castilla and León, University of Valladolid, 42003-Soria, Spain; Department of Pathology, Medical School, University of Alcala de Henares, Madrid, Spain; Laboratory of Neuroanatomy, Institute of Neurosciences of Castilla and León, Valladolid University, Nicolas Rabal Street, 17, 42003-Soria, Spain

ABSTRACT The effects of intracerebral injection of the beta-amyloid protein (A?1-40) on the ?7 subtype of nicotinic acetylcoline receptor protein (nAChR) in neurons of the septum-diagonal band (MS-nDBB) complex were studied in rats. Focal deposition of A? in the retrosplenial cortex resulted in a selective reduction in the number of ?7nAChR-immunoreactive cells in different parts of the MS-nDBB complex, especially in the horizontal nucleus of the diagonal band of Broca (HDB). The analysis revealed a significant decrease of 37.27% in the number of ?7nAChR-immunoreactive cells in the HDB ipsilateral to the A?-injected side as compared to the corresponding hemisphere of non-treated control animals, and a reduction of 31.55% was observed in the HDB ipsilateral to the A?-injected side as compared to the contralateral HDB, which corresponds to the control (PBS)-injected side. A significant reduction (up to 20%) of ?7nAChR-containing neurons was also found in the medial septal nucleus when compared with the corresponding hemisphere in non-treated control animals. The results also revealed that ?7nAChR-positive immunoreactivity is highly localized within cytoplasmic granules in cholinergic neurons and in a small subset of putative GABAergic cells of the MS-nDBB complex. In conclusion, these findings suggest an interaction of A?1-40 with the ?7nAChR, which may contribute to impairments in cholinergic and GABAergic transmission in the MS-nDBB complex.

Keywords: 4 aminobutyric acid receptor, amyloid beta protein, bungarotoxin receptor, calcium binding protein, cholinergic receptor stimulating agent, animal experiment, animal tissue, article, brain nerve cell, cholinergic nerve cell, controlled study, diagonal band of Broca, female, immunocompetent cell, immunoreactivity, nonhuman, protein protein interaction, rat

European Journal of anatomy
ISSN 2340-311X (Online)