Oscillations of Intramuscular pH in Perfused Rat Heart

1973 ◽  
Vol 51 (3) ◽  
pp. 234-238 ◽  
Author(s):  
Naranjan S. Dhalla ◽  
John C. Yates ◽  
Israel Kleinberg
Keyword(s):  
Cardiac Muscle ◽  
Rat Heart ◽  
Cardiac Contraction ◽  
Mechanical Activity ◽  
Heart Metabolism ◽  
Relaxation Cycle ◽  
Perfused Rat Heart ◽  
Isolated Perfused Rat Heart ◽  
Metabolic Stimulation ◽  
Intramuscular Ph

The intramuscular pH of the isolated perfused rat heart fluctuated between 7.11 and 7.14 during each contraction–relaxation cycle; the pH began to decline prior to the onset of cardiac contraction. The observed pH oscillations are independent of the mechanical activity and seem to reflect cyclic fluctuations in heart metabolism during the process of "excitation – metabolic stimulation" in the cardiac muscle.

Effect of extracellular pH on function and metabolism of isolated perfused rat heart

1965 ◽  
Vol 209 (6) ◽  
pp. 1075-1080 ◽  
Author(s):  
Lionel H. Opie
Keyword(s):  
Glucose Uptake ◽  
Flow Rate ◽  
Rat Heart ◽  
Left Ventricular ◽  
Extracellular Ph ◽  
Mechanical Activity ◽  
Perfused Rat Heart ◽  
Isolated Perfused Rat Heart ◽  
Oxidation Rates ◽  
Lactate And Pyruvate

The extracellular pH of the isolated perfused rat heart was varied from 6.9 to 8.0 usually by altering the bicarbonate content of the buffer. Isovolumic left ventricular contractility was measured by an intraventricular balloon. The peak systolic pressure was dependent on the coronary flow rate. At a constant flow rate the peak pressure and cardiac rate were unchanged at 7.4–8.0 but declined at about pH 7.1. The uptake and fate of pyruvate-1-C14 (6 mm) and palmitate-1-C14 (0.7 mm) were similar at pH 7.1–8.0. Compared with pH 7.4, oxidation rates of glucose-U-C14 (5 mm) and acetate-2-C14 (5 mm) were unchanged at pH 7.1, but were greater at pH 8.0. Other increases at pH 8.0 (glucose 5 mm) were in glucose uptake, lactate and pyruvate formation, and the percentage of the glucose uptake accounted for by the sum of C14O2, lactate, and pyruvate formed. It is concluded that in spite of decreased mechanical activity at pH 7.1, Krebs cycle activity is unaltered by pH changes from 7.1 to 8.0, whereas glycolysis and acetate oxidation increase above pH 7.4.

Global ischemic duration and reperfusion function in the isolated perfused rat heart

Resuscitation ◽  
2004 ◽  
Vol 62 (1) ◽  
pp. 97-106 ◽  
Author(s):  
Brian S. Palmer ◽  
Mersiha Hadziahmetovic ◽  
Timothy Veci ◽  
Mark G. Angelos
Keyword(s):  
Rat Heart ◽  
Perfused Rat Heart ◽  
Isolated Perfused Rat Heart ◽  
Ischemic Duration
Sign in / Sign up

Export Citation Format

Share Document