title: P-Glycoprotein Altered Expression in Alzheimer's Disease: Regional Anatomic Variability.
abstract: We investigated the expression of P-glycoprotein (P-gp) in brain samples of Alzheimer disease (AD) and normative brains (NM). Superior temporal cortex hippocampal and brainstem samples from 15 AD and NM brains were selected from comparable sites. P-gp positive capillaries and β-amyloid (Aβ) senile plaques (SP) were counted. Statistical analysis of the data was performed using nonparametric data analysis with Mann-Whitney, Kruskal-Wallis, and Spearman's tests. There were no significant differences in P-gp expression between superior temporal and hippocampus samples. However, there were significant differences in P-gp expression, when comparing brainstem with both hippocampal and superior temporal samples in both conditions (P < 0.012; P < 0.002 in NM cases and P < 0.001; <0.001 in AD cases); the brainstem has greater P-gp expression in each case and condition. In addition, there was a notable inverse negative correlation (P < 0.01) between P-gp expression and the presence of SPs in the AD condition superior temporal cortex. The results of this study suggest that there were significant site-dependent differences in the expression of P-gp. There may be an increased protective role for P-gp expression against amyloid deposition in the brainstem and in the superior temporal cortex of AD brains.
authors: Department of Community Health Sciences, Faculty of Applied Health Sciences, Brock University, 500 Glenridge Avenue, St. Catharines, ON, Canada L2S 3A1.
authors: Brian
authors: B
authors: Jeynes
authors: Department of Pathology & Molecular, Medicine [Neuropathology], Hamilton Health Sciences, McMaster University, Hamilton, 1280 Main Street West, Hamilton, ON, Canada L8S4L8.
authors: John
authors: J
authors: Provias