Sodium ferulate protects against daunorubicin-induced cardiotoxicity in juvenile rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the protect effects of sodium ferulate (SF) on the daunormbicin(DNR-induced cardiotoxicity in juvenile rats.</p><p><b>METHODS</b>Forty male juvenile SD rats were randomly divided into control group (Control), daunorubicin group (DNR), sodium ferudate treatment group (DNR + SF), sodium ferudate group (SF) (n = 10) . Juvenile rats were intraperitoneally treated with DNR (2.5 mg/kg every week for a cumulative dose of 10 mg/kg) preparation immature myocardial injury model in presence with SF (60 mg/kg) oral treat- ment for 25 days. The left ventricular pressure and its response to isoproterenol were measured using left ventricular catheter. Rat myocardium myocardial pathology specimens and ultrastructure changes were also observed. The expression of cardiac Troponin I (cTNI) was detected by Western blot and RT-PCR. Results: SF treatment could inhibit the decreasing of heart rates induced by DNR damage (P < 0.05); it could increase the left ventrivular end diastolic pressure(LVEDP), heart rate, the maximal left ventrivular systolic speed(LVP + dp/dtmax) and the maximal left ventrivular diastolic speed (LVP-dp/dtmax) responding to isoproterenol stimulation(P < 0.01); SF also could improve the myocardial ultrastructure injuries and inhibit the decreasing of cTNI expression caused by DNR damages (P < 0.05).</p><p><b>CONCLUSION</b>SF treatment could alleviate the decreasing of cardiac reservation induced by DNR damages in juvenile rats, which might be related to its reversing the effects on the cardiac systolic and diastolic function injuries and its inhibiting effects on the decreasing of cTNI expression caused by DNR. The mechanism of SF preventing daunorubicin-induced cardiotoxicity in juvenile rats is relevant to inhabited cardiac Troponin I expression.</p>

The application of isoprenaline provocation test on rat model of alcoholic cardiomyopathy / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To study a simple and reliable method to produce the rat model of alcoholic cardiomyopathy, evaluating the model with isoprenaline provocation test (IPT) and morphological indicators.</p><p><b>METHODS</b>Adult male rats were intragastrically infused of wine (52% v/v) at 20 g/(kg x d) for 15 days with the general condition, the change of eating amount and weight being observed. The levels of mean left ventricle systolic pressure (mLVSP), mean left ventricle diastolic pressure (mLVDP), mean left ventricle pressure (mLVP), heart ratio (HR), maximal rise velocity of left ventricular pressure (+ dp/dtmax), maximal fall velocity of left ventricular pressure (- dp/dtmax) and the reaction of isoprenaline were examined by left ventricular cannulation, and the morphological change was observed with optical microscope and transmission electron microscopy.</p><p><b>RESULTS</b>Both diastolic and systolic function of the model rats was lower than that of the control group as well as the cardiac energy reserve induced by IPT. Pathological observation demonstrated myocardial hypertrophy, myocardiocyte necrosis and infiltration of inflammatory cells. The transmission electron microscopy showed that mitochondria became enlarged or crimpled with fused or disappeared cristae and myofibrils dissolved and fractured.</p><p><b>CONCLUSION</b>The adult male SD model rats exhibit diabetic cardiomyopathy by intragastric infusion of wine (52% v/v) at 20 g/(kg x d) for 15 days. IPT can induce the cardiac energy reserve and evaluate that accurately, displaying the hidden heart dysfunction.</p>

Study on the effect of cardioplegia induced by kalium-verapamil-propranolol in different temperatures on the function of immature rat heart / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To explore the appropriate temperature of the kalium-verapamil-propranolol (KVP) cardioplegia by observation of the effect on the function of the immature rat heart.</p><p><b>METHODS</b>Isolated hearts from immature rats were perfused by Langendorff method, and assigned to 1 of the following 5 groups (n = 6-8): control, continuously perfused for 170 min at 36 degrees C, normal temperature, normal perfused for 20 min, changed to perfuse with KVP for 3 min then no perfusion 87 min (ischemia 90 min), followed by 60 min reperfusion. 3 groups of low temperature, perfused for 15 min, cool down to 32 degrees C, 28 degrees C and 24 degrees C especially in 5 min, and at 20th min. heart rate (b/min), tension (g), contraction force (g), peak systolic velocity (dT/dt(max)), peak diastole velocity (dT/dt(max)), coronary flow (Drop/min) were monitored during the whole perfusion.</p><p><b>RESULTS</b>Compared to control group, the heart tension increased after 50 min KVP ischemia. The protection of KVP in normal temperature (36 degrees C) was better than lower temperature (32 degrees C, 28 degrees C, 24 degrees C) such as reducing bad contraction, keeping normal myocardium tension,recovering heart rate, recovering the fuction of contraction force and protecting the coronary flow.</p><p><b>CONCLUSION</b>The KVP cardioplegia in normal temperature has the better effect than that in hypothermia to protect the immature heart.</p>

The effect of different dose of verapamil and propranolol in kalium cardioplegia on the function of immature rat heart / 中国应用生理学杂志

<p><b>AIM</b>To explore the appropriate dose of the verapamil and propranolol in kalium cardiaplegia (KVP) by observation of the effect on the function of ischemic immature rat heart and compared with ST. Thomas II cardiaplegia.</p><p><b>METHODS</b>48 isolated hearts from Sprague-Dawley rats of 60 to approximately 80 g body weight, 22 +/- 2 days, male or female are perfused by Langendorff method for 20 min, and assigned to 1 of the following 6 groups (n = 8): control (CON), continuously perfused for 150 min. Ischemia/reperfusion (I/R), perfused with Locke's solution without glucose and oxygen equilibration for 3 min then no perfusion 27 min, repeated 3 cycles (ischemia for 90 min), followed by reperfusion for 60 min. Ischemia protected with ST. Thomas II cardioplegia (ST), each 3 min perfusion with ST. Thomas II cardioplegia during ischemia. Ischemia protected with three dose KVP cardioplegia (L, M, and H), perfused with ST. Thomas II cardioplegia containing verapamil and propranolol (x 10(-7) mol L(-1)) respectively 2.0, 0.34 (L), 6.8, 1.1 (M), 20,3.4 (H) during each 3 min perfusion of ischemia. Heart rate (min (-1), tens on(g), contraction force(g), peak systolic velocity (g.s-1), peak diastole velocity (g.s-), coronary flow (ml x min(-1 ), re-beat time (s) were monitored during the ischemia/ reperfusion.</p><p><b>RESULTS</b>Compared to CON group, heart tension was rose when ischemia for 40 min and kept higher and could not rebeat after reperfusion in I/R group, In ST group, heart tension was rose after ischemia for 60 min and could re-beat but the pulse was weaker. Compared with ST group, KVP decreased the ischemic cardiac tension in dose dependently and the re-beat was stronger in L, M, and H groups. While compared with CON group, in L group, heart tension was rose when ischemia for 60 min and the re-beat was weaker. In H group, the heart tension was maintained lower when ischemia for 40 min and the re-beat was delay and weaker. Only in M group, heart tension was maintained stable during ischemia for 90 min and re-beat was stronger after reperfusion.</p><p><b>CONCLUSION</b>Kalium cardiaplegia containing verapamil 6.8 x 10(-7) mol x L(-1) and propranolol 1.1 x 10(-7) mol x L(-1) has the best effect to protect the immature heart from ischemic injury.</p>