ciao... uff non riesco a capire come avvenga il rilassamento del muscolo liscio gastro intestinale per stimolazione del recettore alfa-1. Qualcuno può aiutarmi? :( non li trovo scritti da nessuna parte e ho 3 libri di farmacologia : fumagalli, rossi-cuomo e rang-dale.
"In most smooth muscles, the increased concentration of intracellular Ca2+ ultimately causes contraction as a result of activation of Ca2+-sensitive protein kinases such as the calmodulin-dependent myosin light-chain kinase; phosphorylation of the light chain of myosin is associated with the development of tension (Stull et al., 1990). In contrast, the increased concentration of intracellular Ca2+ that result from stimulation of a1 receptors in gastrointestinal smooth muscle causes hyperpolarization and relaxation by activation of Ca2+-dependent K+ channels"