Ca. Walker et al., Temporal endothelin dynamics of the myocardial interstitium and systemic circulation in cardiopulmonary bypass, J THOR SURG, 120(5), 2000, pp. 864-871
Citations number
44
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Objective: Increased systemic levels of the bioactive peptide endothelin 1
during and after cardioplegic arrest and cardiopulmonary bypass have been w
ell documented. However, endothelin 1 is synthesized locally, and therefore
myocardial endothelin 1 production during and after cardiopulmonary bypass
remains unknown.
Methods: Pigs (n = 11) were instrumented for cardiopulmonary bypass, and ca
rdioplegic arrest was initiated. Myocardial interstitial and systemic arter
ial levels of endothelin 1 were measured before cardiopulmonary bypass, thr
oughout bypass and cardioplegic arrest (90 minutes), and up to 90 minutes a
fter separation from bypass. Myocardial interstitial endothelin 1 was deter
mined by microdialysis and radioimmunoassay.
Results: Baseline myocardial endothelin 1 levels were higher than systemic
endothelin 1 levels (25.6 +/- 6.7 vs 8.3 +/- 1.1 fmol/mL, P < .05). With th
e onset of bypass, myocardial endothelin 1 increased by 327% +/- 92% from b
aseline (P < .05), which preceded the increase in systemic endothelin 1 lev
els.
Conclusion: Myocardial compartmentalization of endothelin 1 exists in vivo.
Cardiopulmonary bypass and cardioplegic arrest induce temporal differences
in endothelin 1 levels within the myocardial interstitium and systemic cir
culation, which, in turn, may influence left ventricular function in the po
stbypass period.