New biological properties of coffee melanoidins†
Abstract
Water-soluble melanoidins isolated from roasted coffee induced ex vivo changes in the bioelectric and contractile activity of rat circular gastric smooth muscle tissues. They provoked a depolarization of smooth muscle cellular membranes and an increase in Ca2+-influx as evidenced by the increase in the frequency and amplitude of Ca2+-generated spike potentials. In the presence of 1 × 10−6 mol L−1 acetylcholine and 1 × 10−6 mol L−1 arecoline the melanoidin-evoked contraction was significantly reduced. M-cholinergic receptor blocking agents