The Effect of Local Ischemia on the Ionic Activity of Dog Myocardial Interstitium
During the occlusion of a coronary artery only a small increase in coronary sinus blood H+ and K+ activity has been observed (2, 5). In order to study the real ionic changes in the interstitium of the ischemic myocardium we measured continuously and simultaneously the changes of the H+, Na+ and K+ activity by means of ion sensitive glass microelectrodes (see methods 3, 4,1). A balloon constrictor for transient occlusion was placed around the left descending coronary artery. Up to 7 glass microelectrodes (Ø 50–150/u) were inserted into the region of the left ventricular wall which was obviously supplied by the artery prepared for occlusion. Control electrodes were inserted into other parts of the myocardium. Furthermore we recorded the local myocardial blood flow by means of heated thermocouples, the mean arterial blood pressure, the endexspiratory CO2 concentration, the heart rate, and the ECG. We measured intermittently the arterial pO2, PCO2, pH, and the arterial Na+ and K+ concentration. The experiments were performed on 10 anesthetized, open-chest mongrel dogs weighing 10–20 kg.
KeywordsIonic Activity Left Ventricular Wall Ischemic Region Occlusion Time Glass Microelectrode
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- 1).Benzing, H., G. Gebert, M. Strohm: Ionenverschiebungen im Myokard des narkotisierten Hundes unter verschiedenen Bedingungen. Verh. dtsch. Ges. Kreisl. -Forsch, (im Druck)Google Scholar
- 2).Crampton, R. S., H. A. Roselle, and R. B. Case: Coronary sinus blood pH during myocardial ischemia. Fed. Proc. 25, 4o2 (1966)Google Scholar
- 3).Gebert, G.: Fortlaufende Messung der Aktivität von Alkaliionen im Extracellulärraum der Skeletmuskulatur. Habil. Schrift,Tübingen 1969.Google Scholar
- 5).Kreuziger, H., H. Asteroth und K. Zipf: Kaliumveränderungen nach Herzinfarkt im Tierexperiment. Z. Kreisl.-Forsch. 43, 382–387 (1954)Google Scholar