skip to main content

Title: Physiologic significance of the phosphorylation potential in isolated perfused rat hearts (/sup 31/P NMR)

The authors assessed the metabolic and mechanical effects of changes in coronary perfusion pressure (CPP) and afterload (A) in isolated working apex-ejecting rat hearts perfused with Krebs-Henseleit solution containing an excess of O/sub 2/ and substrate. Log(phosphorylation potential) or log (ATP)/(ADP)x (Pi), designated (L), and log (PCR)/(Pi), designated (L*), were calculated from HPLC measurements after rapid freeze-clamping. Increasing CPP from 80-140 cm H/sub 2/O caused an increase in coronary flow(flow), developed pressure(DevP), O/sub 2/ consumption (VO/sub 2/), L, L*, and CO. L and L* were directly related to VO/sub 2/ and CO. Increasing A from 80-140 cm H/sub 2/O caused an increase in DevP and VO/sub 2/, but a decrease in L, L*, and CO. L and L* were inversely linearly related to VO/sub 2/ but were directly linearly related to CO. In both experiments, L and L* are directly related to CO, suggesting that determination of L* (which can be done with /sup 31/P NMR spectroscopy) may be a useful non-invasive method for determining cardiac pump function curves. L and L* may be related to the Frank-Starling mechanism. In a separate experiment using /sup 31/P NMR spectroscopy of isovolumic (left ventricular balloon) perfused rat hearts, increasing CPP caused amore » direct linear increase in flow, DevP, and L*, confirming the L* results reported above with CPP experiments using the rapid freeze-clamp technique.« less
Authors:
; ; ; ; ; ; ;
Publication Date:
OSTI Identifier:
6991953
Report Number(s):
CONF-8604222-
Journal ID: CODEN: FEPRA
Resource Type:
Conference
Resource Relation:
Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States); Journal Volume: 45:4; Conference: 70. annual meeting of the Federation of American Society for Experimental Biology, St. Louis, MO, USA, 13 Apr 1986
Research Org:
Univ. of California, San Francisco
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; 62 RADIOLOGY AND NUCLEAR MEDICINE; HEART; BLOOD FLOW; NMR SPECTRA; CORONARIES; LIQUID COLUMN CHROMATOGRAPHY; NUCLEAR MAGNETIC RESONANCE; PERFUSED ORGANS; PHOSPHORUS 31; PHOSPHORYLATION; RATS; ANIMALS; ARTERIES; BLOOD VESSELS; BODY; CARDIOVASCULAR SYSTEM; CHEMICAL REACTIONS; CHROMATOGRAPHY; ISOTOPES; LIGHT NUCLEI; MAGNETIC RESONANCE; MAMMALS; NUCLEI; ODD-EVEN NUCLEI; ORGANS; PHOSPHORUS ISOTOPES; RESONANCE; RODENTS; SEPARATION PROCESSES; SPECTRA; STABLE ISOTOPES; VERTEBRATES 550201* -- Biochemistry-- Tracer Techniques; 550600 -- Medicine