Contractile responses to electrolyte changes during coronary bolus perfusion. A comparative study in isolated rat, guinea pig, and rabbit hearts
Autor: | Per Jynge, Holten T, Jan Schjøtt, Audun N. Øksendal, Blankson H |
---|---|
Rok vydání: | 1995 |
Předmět: |
Inotrope
Coronary angiography Male medicine.medical_specialty Time Factors Iohexol Guinea Pigs Electrolyte Guinea pig Electrolytes Bolus (medicine) Species Specificity Internal medicine medicine Animals Radiology Nuclear Medicine and imaging Rats Wistar Electrolyte regulation Analysis of Variance Chemistry General Medicine Coronary Vessels Myocardial Contraction Electric Stimulation Rats Perfusion Endocrinology Rabbits medicine.drug |
Zdroj: | Investigative radiology. 30(3) |
ISSN: | 0020-9996 |
Popis: | RATIONALE AND OBJECTIVES: The authors studied cardiac contractile responses during coronary bolus perfusion, as in coronary angiography, in three species and related the responses to the bolus content of electrolytes and to patterns of cardiac electrolyte regulation. METHODS: Isolated, paced hearts from the rat, guinea pig, and rabbit were subjected to coronary perfusion in the global mode with recording of left ventricular developed pressure during exposure (< 7.5 seconds) and recovery (30 seconds). RESULTS: In series 1 of the experiments, the perfusate reduction to one fifth of normal Ca, Na, K, Mg, and Ca/Na/K/Mg, and the removal of all ions, led to the following percentage changes in left ventricular developed pressure: rat -64, +84, -38, +7, +40, and +79; guinea pig -43, +48, +18, +5, +28, and +37; and rabbit -32, +60, +14, +4, +22, and +33. CONCLUSIONS: Except for K reduction, inducing negative inotropy in the rat but positive inotropy in the guinea pig and the rabbit, the three species responded similarly. Thus, changes in left ventricular developed pressure were related to changes in direction and rate of the sarcomal Na-Ca exchange. In series 2 of the experiments, iohexol (150 mg I/mL) +/- minor electrolyte additives were studied. Additives with Na 30 mmol/L only or with Na, Ca, K, and Mg carefully balanced reduced positive and negative inotropic responses in all three species. |
Databáze: | OpenAIRE |
Externí odkaz: |