Effects of oligomycin and acidosis on rates of ATP depletion in ischemic heart muscle.

Abstract

The perfusion of canine cardiac muscle with 10 microM oligomycin produced a nearly 90% slowing of the net rate of tissue ATP depletion from 0.200 to 0.025 mumol X min-1 X g wet wt-1 of tissue during a subsequent myocardial autolytic interval during which tissue pH was held constant. Moreover, lowering the tissue pH during the autolytic process by 0.6 unit from approximately 6.8 to approximately 6.2 produced a nearly 60% slowing of the net rate of tissue ATP depletion from 0.200 to 0.087 mumol X min-1 X g wet wt-1. The pH dependence of the net rate of tissue ATP depletion (by an oligomycin-sensitive process) was that predicted from the mitochondrial ATPase pH-inhibition profiles reported earlier (J. Biol. Chem. 258: 9657-9661, 1983). When taken together with our observation that the mitochondrial ATPase comprises approximately 90% of the total of all of the ATP hydrolyzing activities present in cardiac muscle cells, data reported here suggest that the protonic inhibition of the mitochondrial ATPase plays a major role in regulating the rate of tissue ATP depletion during myocardial ischemia.

• Authors: W Rouslin, J L Erickson, R J Solaro
• Journal: The American journal of physiology (Am J Physiol) Vol. 250 Issue 3 Pt 2 Pg. H503-8 (Mar 1986) ISSN: 0002-9513 [Print] United States
• PMID: 2937313 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Oligomycins
• Adenosine Triphosphate
• Adenosine Triphosphatases
• HEPES

Topics

• Acidosis (metabolism)
• Adenosine Triphosphatases (metabolism)
• Adenosine Triphosphate (metabolism)
• Animals
• Autolysis (enzymology, metabolism)
• Coronary Disease (metabolism)
• Dogs
• Female
• HEPES (pharmacology)
• Hydrogen-Ion Concentration
• Male
• Mitochondria, Heart (enzymology)
• Myocardium (metabolism)
• Myofibrils (enzymology)
• Oligomycins (pharmacology)