Effect of PACAP38 on loss of olfactory neurons because of copper chelation. A, DDC induces dose-dependent neuron loss. Top, Primary cultures were treated for 2 d with the indicated concentration of DDC. Neurons (NST-positive cells) and glial cells (GFAP-positive cells) were counted. Bottom, Immunofluorescence using the amidated PACAP38 antibody identified loss of PACAP amidation in surviving glial cells with DDC treatment. B, PACAP38 rescues a subpopulation of DDC-treated neurons. Primary cultures treated with 0.2 μm DDC had significantly decreased numbers of neurons. Coaddition of 10−8mPACAP38 (PAC) with DDC rescued ∼35% of the neurons (unpaired Student's t test of PACAP treatment relative to treatment with 0.2 μm DDC alone, **p < 0.001).
