j Mol Cell Cardiol 19 (Supplement III) (1987)

151 THE ROLE OF PULMONARY VASCULAR RESPONSE ON RIGHT VENTRICULAR PERFORMANCE IN

CONGESTIVE HEART FAILURE. S. G. Lage; J. A. F. Ramires; M. Rati; G. Bellotti; F. Pileggi. Heart Institute - University of S$o Paulo - Brazil

The pulmonary vascular response to exercise and its influence on Right Ventricular (RV) performance was studied in th i r ty

nine Congestive Fleart Failure (CHF) patients (pts.). According NYHA two groups were analysed: A - Mild CHF (19 pts.

class I / II); B - Severe CHF (20 pts. class III / IV). They were evaluated by hsmodynamic (H) study at rest (R) an d during

supine exercise (E), on cicloergometsr with progressive loads unti l the maximal effort (A = 75 w; B = 48 w). The Swan - - Ganz catheter was introduced in pulmonary artery and Sones in aorta to register H data. Arterial blood samples were collected to Plasma Renin Activi ty (PRA) analysis. Respective R and E data to group A and B were: FIR (heart rate, bpm)

77 -+ 15 and 122 +- 15; 92 ,+ 11 and 126 + 16" * ; RAP (right atrial pressure, mmHg) 3 ,+ 2 and 4 -+ 3; 12 -+ 9 and 23 + 12 *~, PWP (pulmonary wedge pressure, mmHg) 8 • 4 and 13 -+ 7; 29 "+ 8 and 33 -+ 7 *~, CI (cardiac index, I/min. m ~) 2. 5 '+ 0 . 7 and 4. 5 + 1.4; 1.3 +- 0 .6 and 1 .8 "+ 0 .8 "~ , PAR ( pulmonary arteriolar resistance, d y . s/cm 5) 205 -+ 128 and 148 '+ 103; 526 + 377 and 743 -+ 435 *~, SVR (systemic vascular rssistance, dy,s/cm s) 2078 -+ B00 and 1314 -+ 455; 3468 +- 1441 and 2719 +- 1446 *~, PRA(~g/ml/b) 1 .74 +- 1.11 and Z 2 4 -+ 1.51;

3. 11 -+ 1. 93 and 4. 04 • 1 . 9 0 " (WilksStatistic: * p < 0 .05; * * p < 0.01). Conclusion: 1- Group B showed

higher PAR and SVR at rest than group A; during exercise (B) PAR and RV dysfunction increased; 2- The high PRA in

B (R and E) represented R - A - A axis exacerbation and could be important on high PAR and SVR in severe CHF.

152 MOLECULAR CHANGES IN CARDIAC MEMBRANES DURING ISCHEMIA-REPERFUSION. J.M.J. Lamers, J. Blom, J.H. Rartog a, P.D. Verdouw a, J.A. Post b, A.J. Verkleij b. Departments of Biochemistry I and Thoraxcentre a, Erasmus University, Rotterdam and Institute of Mole- cular Biologyb,State University of Utrecht, Utrecht, The Netherlands.

Studies were undertaken to investigate changes in membrane structure and function after ischemia and reperfusion. Isolated sarcolemma (SL) and sarcoplasmic reticulum (SR) vesicles contain Ca2+ transport regulating phosphoproteins (i.e. phospholamban), which become poor substrates for proteinkinases during ischemia-reperfusion. The lat- ter change and the ATP depletion could be causing a reduced Ca2+ extrusion rate, whereas the involvement of membrane accumulation of lipidamphiphiles may be minor. Dietary polyunsaturated fatty acids (i.e. fish oil) produce marked changes in the fatty acid composition of SL membrane phospholipids, but the composition remains unaf- fected during ischemia-reperfusion. The increased membrane content of polyene fatty acids, which are most susceptible to free radical-induced peroxidation, has no effect on the short-term recovery of heart function. Reorganization of phospholipids, lateral phase separation and fusion events, all induced by changes in the ionic environment of the phospholipidbilayer, appear to be more critical to the integrity of cardiac membranes during ischemia and reperfusion and are related to the long-term recovery of regional heart function after a period (30 and 60 min) of coronary ligation. (supported by the Foundation for Medical Research Medigon)

153 D-(-)-3-HYDROXYBUTYRATE PROTECTS THE GLOBAL FUNCTION OF THE LEFT VENTRICLE FROM DETE- RIORATION DURING ACUTE REGIONAL ISCHEMIA. J. Lammerant, T. Huynh-Thu, J. Kolanowski. Department of Physiology, FNDP School of Medicine, B-5000 Namur, Belgium.

The D-(-) isomer or natural form of 3-hydroxybutyrate (D-(-)-3OHB) is taken up by the acutely isehemic myocardium (Lammerant et al., J Mol Cell Cardiol 18, 759-763, 1986). Since, in contrast to glucose, D-(-)-3OHB can enter mitochondria directly, it could be appropriate to maintain the residual aerobic ATP production in the face of a declining glycolytic flux and, hence, protect the function of the left ventricle (LV) from deterioration during acute regional ischemia. A mechanical benefit of infusing this ketone was observed in 13 anesthetized intact dogs submitted to an occlusion of the left anterior descending coronary artery (balloon catheter), followed 40 min later by a 90 min infusion of arginine D-(-)-3OHB (20 ~mol/kg.min, iv) which raised the ar- terial ketonemia up to 1,136 ~ 65 ~M. After 90 min ketone treatment, LV peak positive dP/dt, output per min, and minute work did not differ from their pre-infusion (30 min ischemia) values. By comparison (three-way variance analysis) with the down course ob- served in 13 control ischemic dogs, the ketone treatment significantly stabilized the time course of LV peak positive dP/dt (P < 0.00|), output per min (P < 0.0|), and mi- nute work (P < 0.001) which, in the control dogs, decreased by an average of 22 + 5, 26 ~ 5, and 34 + 6 per cent, respectively. The stabilizing effect of arginine D-Y-)- 30HB upon the t~me course of global LV function was not attributable to the infused arginine since it was not observed with equimolar infusions of the amino acid alone.

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