Muscarinic acetylcholine receptor is involved in acetylcholine regulating stomatal movement

In animal cells, action of acetylcholine depends on its binding with its tw o specific receptors on the plasma membrane: the nicotinic and muscarinic r espectively. The present investigation has shown that agonists of muscarini c receptor (muscarine) could induce stomatal opening, while the antagonists (atropine) could block stomatal opening induced by acetylcholine. Their ef fects can only be realized in medium containing Ca2+, but not in medium con taining K+. The results tend to reveal that the muscarinic receptor is invo lved in acetylcholine-induced stomatal movement.