European Journal of Anatomy

Official Journal of The Spanish Society of Anatomy
Cover Volume 6 - Number 2
Eur J Anat, 6 (2): 95-107 (2002)

Alteration of cholinergic, excitatory amino acid and neuropeptide markers in the septum-diagonal band complex following injections of fibrillar ?-amyloid protein into the retrosplenial granular cortex of the rat

Gonzalo-Ruiz A., Sanz J.M.

Laboratory of Neuroanatomy, Inst. of Neurosci. of Castilla/Leon, University of Valladolid, Nicolas Rabal Street, 17, 42003-Soria, Spain

ABSTRACT The effects on cholinergic, excitatory amino acid and neuropeptide markers in the basal forebrain of an intracerebrally-injected synthetic peptide corresponding to the first 1-40 amino acids of beta-amyloid protein (A?1-40) was studied in rats. Focal deposition of A? in the retrosplenial granular cortex resulted in a significant loss of cholinergic and glutamate-immunoreactive neurons in the septum-diagonal band complex. The medial septal nucleus showed a reduction of 39% ± 1% in the number of cholinergic neurons and a significantly reduced number of cholinergic neurons (up to 22% ± 10%) was also found in the horizontal nucleus of the diagonal band of Broca in comparison with the same paramaters in uninjected controls. A markerd loss of glutamate-containing neurons was also found in the medial septal nucleus (up to 19% ± 6%) together with a decrease of approximately 22% ± 3% in the horizontal nucleus of the diagonal band of Broca when compared with uninjected control animals. Furthermore, a moderate reduction in fibres and structures such as terminals immunoreactive for glutamate, substance P, and neurotensin was observed in the septum-diagonal band complex. These results show that two different neurochemically defined populations of neurons in the basal forebrain are affected by the neurotoxicity of A? in vivo.

Keywords: amyloid beta protein, biochemical marker, excitatory amino acid, glutamic acid, neuropeptide, neurotensin, substance P, Alzheimer disease, animal experiment, animal tissue, article, cholinergic nerve, controlled study, diagonal band of Broca, female, forebrain, immunocompetent cell, intracerebral drug administration, neurochemistry, neurotoxicity, nonhuman, rat, septum nucleus

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