Abstract
The effect of a short 4 second ultrasound application (1.0 W/cm2 SATA at 963 KHz) on the post-tetanic-potentiation of isolated isometrically contracting rat papillary muscle has been evaluated. Post tetanic-potentiation was produced in hypoxic isolated papillary muscle by interrupting the control stimulation rate of 6/minute with 10 stimulating pulses at 0.2 sec intervals for one cycle. Ultrasound application varied from one second prior to the stimulating train to a period covering the entire train. Ultrasound application just preceding and impinging upon the pulse train, enhanced post-tetanic-potentiation contractions. However, delay in ultrasound application and covering the stimulating pulse train, reduced post-tetanic-potentiation contractions. These data suggest that a window exists for the effects of ultrasound on contracting myocardium which may be used to probe critical events in the cardiac cycle.
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Forester, G.V., Mortimer, A.J., Roy, O.Z. et al. Effect of brief ultrasound exposure on post-tetanic potentiation in cardiac muscle. Pflügers Arch. 400, 208–210 (1984). https://doi.org/10.1007/BF00585044
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DOI: https://doi.org/10.1007/BF00585044