Contractions of Intestinal Smooth muscles When slow waves above threshold, it triggers APs bi opening of VG Ca2+ channels ° Inward flow of ca2+ Produces the upward depolarization phase Stimulates contraction of smooth muscle Repolarization VG K channels open Slow waves decrease in amplitude as they are conducted May stimulate contraction in proportion to the magnitude of depolarization6 • When slow waves above threshold, it triggers APs by opening of VG Ca2+ channels. • Inward flow of Ca2+: • Produces the upward depolarization phase. • Stimulates contraction of smooth muscle. • Repolarization: • VG K+ channels open. • Slow waves decrease in amplitude as they are conducted. • May stimulate contraction in proportion to the magnitude of depolarization. Contractions of Intestinal Smooth Muscles