Action Potential and Its Properties in Skeletal and Smooth Muscle

Description

Action potentials in skeletal and smooth muscle initiate contraction but differ in properties. In skeletal muscle, action potentials are rapid, short (2–5 ms), and follow the all-or-none principle, leading to quick, forceful contractions. Smooth muscle action potentials are slower, longer-lasting, and may have plateau phases or spontaneous rhythmicity. Smooth muscle can generate graded responses and is modulated by hormones and stretch. Both types involve ion fluxes—mainly Na⁺ and K⁺ in skeletal, and Ca²⁺ and K⁺ in smooth muscle.