[Age dependence of spontaneous frequencies and intracardial Baindridge-effect of rabbits between the 3rd and 18th day of life].
With continuous perfusion at defined intraluminal pressures isolated right atria from rabbits were examined. Age groups of 3-6, 9-12 and 15-18 days of life were used to measure the chronotropic response to change of atrial pressure over a range of 0.1 to 0.9 kPa (10-90 mm H2O). At transmural pressure of 0.1 kPa (control) the rate of spontaneously beating atria decreased progressively with age over the first three weeks. As compared to the group of 15-18 days, for each intraluminal pressure the atrial rate was significantly higher in the group of 3-6 days. Already 3-6 days after birth the chronotropic self-control mediated by stretch (Bainbridge effect) was present, this response did not vary significantly from that obtained in the group of 15-18 days of life.
Cermak
M
M
Carl-Ludwig-Institut für Physiologie, Karl-Marx-Universität Leipzig.
Rossberg
F
F
D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D016275:Atrial Function; D006339:Heart Rate; D011312:Pressure; D011817:Rabbits
Zur Altersabhängigkeit von Spontanfrequenz und intrakardialem Bainbridge-Effekt von Kaninchen zwischen dem 3. und 18. Lebenstag.