These indices were taken from 72 AP records from 12 guinea pigs. When the concentration of the magnesium ion in the perfusate was reduced to0.6 mmol/L,the average values of APD_(30mv) and APD_(100) decreased to 80.7%and 83% respectively of the control.

• 当灌注液中镁离子浓度减低到0.；6mol/L 时；72次 AP 的 APD_(_30mv)和APD_(100)分?e为对照值的80