Figure 1. The PGE₂ EP3 receptor is expressed in AD and in mouse brain.

(A)400X magnification of human control and AD temporal cortex, layers II/III, demonstrates EP3 receptor expression in multiple cell types. In control temporal cortex, EP3 receptor is expressed at low levels in neuronal soma (horizontal arrow), and at higher levels in apical dendrites (diagonal double arrows). In AD temporal cortex, EP3 receptor is expressed in neurons and apical dendrites (horizontal arrow), as well as in cells morphologically consistent with astrocytes (arrowheads) surrounding an amyloid plaque (small arrows in a circle). Enlargements (bottom right) show EP3 receptor present in a perinuclear distribution and in a neuronal apical dendrite (arrow), and in astrocytes (arrowheads; scale bar=10μm). Negative control sections showed no background staining (bottom left panel). (B) Quantitative Western analysis of temporal cortex of control, MCI, and AD post-mortem tissues (n=3 per group) demonstrates increased expression of EP3 receptor in MCI and a further increase in AD (*p<0.05; **p<0.01). (C) qPCR of hippocampal EP3 receptor mRNA derived from aging 3 mo, 6 mo, and 12 mo non-transgenic (WT) and APPSwe-PS1 ΔE9 (APPS) mouse hippocampus demonstrates a significant induction in expression between 6 mo and 12 mo in APPS but not wild type mice (n=6 per group, *p<0.05; **p<0.01).