Effect of L-type Ca²⁺ channel activators and blockers on A_2AR mRNA and protein levels in PC12 cells.

<p>(<b>A</b>) The L-type Ca²⁺ channel activator Bay K8644 increased A_2AR mRNA levels in PC12 cells compared to untreated controls while the L-type Ca²⁺ blocker Nifedipine, as well as SMF exposure, decreased A_2AR mRNA levels after 6.0 h of exposure (<i>p</i><0.05 for each test condition compared to control for n≥3 independent experiments). (<b>B</b>) Increased A_2AR mRNA resulting from exposure to Bay 8644 was reversed by concomitant exposure to SMF (<i>p</i> values are shown for n≥3 independent experiments).