Pacing-induced transient depolarizations in rabbit atrial myocardium.

نویسندگان

  • B Nilius
  • W Boldt
چکیده

Transient afterdepolarizations (TD) were analyzed following a train of paced action potentials in isolated pectinate muscles bordering the crista terminalis in rabbit right atria. After cessation of a rapid drive TD peaked between 400 and 700 ms. The amplitude of TD were found to be pacing-dependent (maximum at 250 ms pre-drive pacing interval 12.9 +/- 2.2 mV, n = 27). At pacing intervals longer than 1000 ms no TD could be observed but pacing intervals shorter than 250 ms provoked a triggered activity. Verapamil (13.2 X 10(-6) mol.1(-1) completely blocked pacing-induced TD. TD could be described quantitatively using a model of the transient inward current.

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عنوان ژورنال:
  • General physiology and biophysics

دوره 3 2  شماره 

صفحات  -

تاریخ انتشار 1984