VOL. 3, No. 1, January 2006

F. Ricci, et al. [2006] Med Hypotheses Res 3: 605-613.

Expression of Neuronal Nitric Oxide Synthase in
PDGF-hAPP Transgenic Mice

F. Ricci, E. Borsani, A. Stacchiotti, R. Rezzani, C. Mariani,
R. Bianchi and L. F. Rodella*

Abstract. The major histopathological finding in the Alzheimer’s disease (AD) brain is
the presence of neuritic plaques containing beta-amyloid (Abeta). In addition some findings
showed an alteration of nitric oxide pathway in AD patients. PDGF-hAPP mice, an animal
model of AD, deposit Abeta in age-dependent manner, were used as. In this study, we
investigated the neuronal nitric oxide synthase (nNOS) expression in the cortex of transgenic
PDGF-hAPP mice comparing with C57BL/6 control. We also detected neuropeptide Y
(NPY), known to be co-localised with NOS in cortical neurons, and neuN, a neuronal
marker. Our results showed a significant decrease in the number of nNOS positive neurons
in the cortex of transgenic mice respect to control. NADPH-d/NPY double staining showed
that almost all nitroxidergic neurons were co-localized with NPY and that several neurons
were only NPY positive. Respect to control, transgenic mice showed a decrease of NADPH-
d/NPY double stained neurons and an apparent increase of NPY single stained neurons. The
total number of neuN positive neurons was similar in both groups, suggesting that in some
double stained neurons there was a nNOS down-regulation but that the neurons survived
expressed only NPY. These data support that nitroxidergic system is impaired in this AD
animal model.

*Address all correspondence to: Prof. L.F. Rodella, Department of Biomedical
Sciences and Biotechnology, Unit of Human Anatomy, University of Brescia, Viale Europa,
11 25123 Brescia, Italy. Phone: +39-030-3717485. Fax: +39-030-3717408.

Full Text PDF