Protective effects of antioxidative serotonin derivatives isolated from safflower against postischemic myocardial dysfunction.
N-(p-Coumaroyl)serotonin (C) and N-feruroylserotonin (F) with antioxidative activity are present in safflower oil. The protective effects of C and F were investigated in perfused guinea-pig Langendorff hearts subjected to ischemia and reperfusion. Changes in cellular levels of high phosphorous energy, NO and Ca2+ in the heart together with simultaneous recordings of left ventricular developed pressure (LVDP) were monitored by an nitric oxide (NO) electrode, fluorometry and 31P-NMR. The rate of recovery of LVDP from ischemia by reperfusion was 30.8% in the control, while in the presence of C or F a gradual increase to 63.2 or 61.0% was observed. Changes of transient NO signals (TNO) released from heart tissue in one contraction (LVDP) were observed to be upside-down with respect to transient fura-2-Ca2+ signals (TCa) and transient O2 signals detected with a pO2 electrode. At the final stage of ischemia, the intracellular concentration of Ca2+ ([Ca2+]i) and the release of NO increased with no twitching and remained at a high steady level. The addition of C increased the NO level at the end of ischemia compared with the control, but [Ca2+]i during ischemia decreased. On reperfusion, the increased diastolic level of TCa and TNO returned rapidly to the control level with the recovery of LVDP. By in vitro EPR, C and F were found to directly quench the activity of active radicals. Therefore, it is concluded that the antioxidant effects of two derivatives isolated from safflower play an important role in ischemia-reperfusion hearts in close relation with NO.
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D031187:Carthamus tinctorius / Q000737:chemistry*; D003331:Coronary Vessels / Q000187:drug effects / Q000503:physiopathology; D004578:Electron Spin Resonance Spectroscopy; D005260:Female; D005609:Free Radicals / Q000378:metabolism; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects / Q000503:physiopathology; D066298:In Vitro Techniques; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008854:Microscopy, Electron; D009200:Myocardial Contraction / Q000187:drug effects; D017202:Myocardial Ischemia / Q000188:drug therapy* / Q000503:physiopathology*; D015425:Myocardial Reperfusion; D009569:Nitric Oxide / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology; D020011:Protective Agents / Q000494:pharmacology*; D012701:Serotonin / Q000031:analogs & derivatives* / Q000494:pharmacology*
D000975:Antioxidants; D005609:Free Radicals; D010936:Plant Extracts; D020011:Protective Agents; D009569:Nitric Oxide; D012701:Serotonin; D002118:Calcium