Effects of hydrogen sulphide on ischaemia-reperfusion injury and ischaemic preconditioning in the isolated, perfused rat heart.
OBJECTIVE
Hydrogen sulphide (H(2)S) protects the heart against ischaemia-reperfusion injury caused by low flow or local ischaemia. We hypothesised that: (1) H(2)S protects against global ischaemia-reperfusion injury of the heart, (2) H(2)S plays a mechanistic role in ischaemic preconditioning, and (3) H(2)S acts by phosphorylation of protein kinases.


METHODS
Isolated, perfused rat hearts were used in two series. Series 1: group 1.1 (n=10), 40 min of ischaemia and 120 min of reperfusion, group 1.2 (n=7), like 1.1 except that 40 microM NaHS was added to the perfusate during stabilisation and throughout the experiment. Group 1.3 (n=10), like 1.1, but endogenously produced H(2)S was blocked by D,L-propargylglycine. Series 2: group 2.1 (n=10) control, 30 min of ischaemia followed by 120 min of reperfusion. Group 2.2 (n=10) ischaemic preconditioning before sustained ischaemia and 120 min of reperfusion. Group 2.3 (n=10) like 2.2 except of D,L-propargylglycine treatment like in group 1.3. Mitogen activated protein kinases including extracellular signal-regulated kinases (ERK 1/2), the stress-activated/c-Jun NH2 terminal kinases (JNK), P38, as well as protein kinase B/AKT (AKT), adenosine monophosphate dependent protein kinase (AMPK) and the inducible heat shock protein 72 were measured by Western blotting. Adenine nucleotides (ATP, ADP, and AMP) were measured by high-pressure liquid chromatography and energy charge was calculated.


RESULTS
Infarct size was increased by D,L-propargylglycine (40+/-6 vs 27+/-10% in controls, p=0.03, Bonferroni post hoc test). There was a non-significant decrease in infarct size in the NaHS group (to 20+/-13%). Western blot analysis indicated an upregulation of heat shock protein 72 in the NaHS treated group and a reduced phosphorylation of AKT in the D,L-propargylglycine group. D,L-propargylglycine had no effect on ischaemic preconditioning or on phosphorylation of protein kinases (ERK, AKT, P38, JNK and AMPK) in preconditioned hearts. No difference in energy charge was found between groups, although ADP was increased in the NaHS-treated group.


CONCLUSIONS
Endogenous H(2)S production protects against global ischaemia, and H(2)S may be a part of the endogenous cell defence. However, endogenous H(2)S did not appear to be important in ischaemic preconditioning, and protein kinases were not important for the effect of H(2)S. Exogenous H(2)S may provide myocardial protection, possibly acting by expression of heat shock protein 72.
Bliksøen
Marte
M
Institute of Experimental Medical Research, Faculty Division, Ullevål University Hospital, University of Oslo, Oslo, Norway.
Kaljusto
Mari-Liis
ML
Vaage
Jarle
J
Stensløkken
Kåre-Olav
KO
D000818:Animals; D015153:Blotting, Western / Q000379:methods; D002316:Cardiotonic Agents / Q000627:therapeutic use*; D004353:Drug Evaluation, Preclinical; D050884:HSP72 Heat-Shock Proteins / Q000378:metabolism; D006862:Hydrogen Sulfide / Q000627:therapeutic use*; D019157:Ischemic Preconditioning, Myocardial / Q000379:methods*; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D008297:Male; D009203:Myocardial Infarction / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control; D009924:Organ Culture Techniques; D010766:Phosphorylation / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D015427:Reperfusion Injury / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D016277:Ventricular Function, Left / Q000187:drug effects; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
D002316:Cardiotonic Agents; D050884:HSP72 Heat-Shock Proteins; D048031:JNK Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D006862:Hydrogen Sulfide