Frank-Starling Mechanism: There was no significant trend observed in ventricular contractile force in response to increasing imposed length of the heart (Fig 1a). A maximum ventricular contractile force of 0.0032 + 0.001039 N (N=3) was generated at an imposed length of 4 mm. A minimum ventricular contractile force of 0.00137 + 0.0000577 N (N=3) was generated at an imposed length of 0 mm.
There was no significant trend observed in heart rate in response to increasing imposed length of the heart (Fig 1b). A minimum heart rate of 31.7 + 0.577 beats/min (N=3) was generated at an imposed length of 7 mm. A maximum heart rate of 36.7 + 0.577 beats/min (N=3) was generated at an imposed length of 6 mm.
Autonomic Control of the Heart: A significant decrease in …show more content…
2b). A minimum heart rate of 33.7 + 0.577 beats/min (N=3) was observed with no additions. After the addition of ephinephrine, a significant increase in heart rate from 33.7 + 0.577 beats/min (N=3) to 37.7 + 0.577 beats/min (N=3) was observed. After the addition of eserine, no significant difference in heart rate was observed relative to the baseline value. Following the addition of atropine, a significant increase in heart rate from 33.7 + 0.577 beats/min (N=3) to 37.7 + 0.577 beats/min (N=3) was observed. No significant difference in heart rate was observed after the addition of acetylcholine relative to the baseline value. The maximum heart rate of 37.7 + 0.577 beats/min (N=3) was both observed after the addition of ephinephrine and