When the membrane potential reaches approximately – 60 mV , the K channels close and the Na channels open and the prepotential phase begins again . When the membrane potential reaches approximately − 60 mV , the K channels close and Na channels open , and the prepotential phase begins again .
Apabila potensi membran mencapai kira-kira  60 mV, saluran K ditutup dan saluran Na terbuka dan fasa potensi bermula lagi. Apabila potensi membran mencapai kira-kira  60 mV, saluran K ditutup dan saluran Na terbuka, dan fasa potensi bermula lagi.