A comparative study was performed of the permeability of cell membranous structures in canine stunned myocardium and that of infarct myocardium by using colloidal lanthanum nitrate as an ultrastructure probe. Stunned ...A comparative study was performed of the permeability of cell membranous structures in canine stunned myocardium and that of infarct myocardium by using colloidal lanthanum nitrate as an ultrastructure probe. Stunned myocardium was characterized by mitochondrial swelling, vacuolar formation, a few lanthanum granules deposrting inside cells and intact structure of such membranes as cell membrane, mitochondrial membrane and lysosome membrane.Infarct myocardium was characterized by a large number of lanthanum granules passing through ruptured cell membrane and depositing in the cytoplasm and mitochondria. These results suggest that membranous structure remained intact during the occurrence of stunned myocardium.展开更多
Objective:To observe the effects of inhibition of glycolysis with iodoacetate (IAA) on calcium homeostasis and functional recovery of stunned myocardium in anesthetized dogs. Methods: Atomic absorption spectrophotomet...Objective:To observe the effects of inhibition of glycolysis with iodoacetate (IAA) on calcium homeostasis and functional recovery of stunned myocardium in anesthetized dogs. Methods: Atomic absorption spectrophotometry was employed to measure myocyte calcium and magnesium contents. Hemodynamics were monitored with a multichannel electrophysiologic recorder. Results: In nonischemic canine hearts (control), IAA's inhibition of glycolysis failed to change the [Ca2+] and [Mg2+] levels and cardiac functional conditions, whereas in hearts subjected to 15-minute ischemia , [Ca2+] increased from nonischemic 1.40±0. 20μmol/g to ischemic 1.80±0.17 μmol/g (P<0. 05), while [Mg2+] decreased. After 30 min of reperfusion,[Ca2+] continued to increase from 1.57±0.21 μmol/g (nonischemic area)to 2. 26±0. 09 μmol/g (abnormal area) and 60 min of reperfusion saw a slight restoration (1.54±0. 16 μmol/g in nonischemic area and 2. 21±0.20 μmol/g in abnormal area). In the glycolysis-inhibiting group, the calcium level registered a significant rise after 30 min of reperfusion: 1.57±0.07 μmol/g in nonischemic area and 2. 90? 0.25 μmol/g in abnormal area (P<0. 01).There was a significant difference between the glycolysis-inhibiting group and the group to which IAA was not applied. [Mg2+] maintained at a relatively low level and registered a more remarkable drop during inhibition of glycolysis, P<0.01 in comparison with the non IAA-administered group,suggesting that inhibition of glycolysis could cause severe calcium overload to sustain, in addition to an obvious harm to cardiac function. Left ventricular end-diastolic pressure and diastolic factor T were augmented andp/dt(max)declined. Conclusion: Since in vivo inhibition of glycolysis seemed to lead to severe calcium overload and hemodynamics changes,it might indicate that glycolysis played an importent role in the restoration of calcium homeostasis in postischemic myocardium,and that ATP derived from glycolysis took a significant part in myocardial ion transport both at the stage of ischemia and the early stage of reperfusion and in cardiac functional recovery.展开更多
This is a report of a study on the protective effect of berberine(Ber) on postischemic myocardial stunning and the role it plays in ATPase activity. Isolated working rat hearts were used with global ischemia for 30 mi...This is a report of a study on the protective effect of berberine(Ber) on postischemic myocardial stunning and the role it plays in ATPase activity. Isolated working rat hearts were used with global ischemia for 30 min followed by reperfusing for 40 min. Both systolic and diastolic functions of stunned myocardium were significantly decreased. The recovery of LVSP×HR and CO was 52%±8% and 40%±8% respectively; LVEDP and T were elevated; while both Na +, K +ATPase activity and Ca 2+ , Mg 2+ ATPase activity of myocardial membrane and mitochondria were depressed. Berberine(25 mg·kg -1 ·d -1 , ip, 3 d, and 10 μmol L -1 for isolated heart perfusion) was able to enhance the percent recovery of LVSP×HR and CO to 85%±12% and 75%±11%, respectively, and reduce LVEDP from 298%±64% to 166%±44%, with an improvement in myocardial membrane Na +, K +ATPase activity and mitochondria Ca 2+ , Mg 2+ ATPase activity. This study suggested that berberine can protect cardiac function from ischemia reperfusion stunning injury by preserving ATPase activity in ischemic myocardium.展开更多
BACKGROUND Cardiac injury may occur after acute pathology of central nervous system(CNS)without any evidence of primary cardiac diseases.The resulting structural and/or functional changes are called cerebrocardiac syn...BACKGROUND Cardiac injury may occur after acute pathology of central nervous system(CNS)without any evidence of primary cardiac diseases.The resulting structural and/or functional changes are called cerebrocardiac syndrome(CCS).The great majority of studies have been performed in patients with subarachnoid hemorrhage(SAH),while CCS data after intracerebral hemorrhage(ICH)are rare.It may cause diagnostic and therapeutic pitfalls for the clinician due to a lack of specific clinical manifestations and diagnostic methods.Understanding the underlying pathophysiological and molecular mechanism(s)following cerebrovascular incidents will help to implement prevention and treatment strategies to improve the prognosis.CASE SUMMARY A 37-year-old man with a history of hypertension presented to our department on an emergency basis because of a sudden dizziness and left limb weakness.Cerebral computed tomography(CT)suggested ICH in the occipital and parietal lobes,and the chosen emergency treatment was hematoma evacuation.Left ventricular(LV)dysfunction occurred after the next 48 h and the electrocardiogram(ECG)showed non-ST elevation myocardial infarction.CCS was suspected first in the context of ICH due to the negative result of the coronary CT angiogram.CONCLUSION Misinterpretation of ischemic-like ECGs may lead to unnecessary or hazardous interventions and cause undue delay of rehabilitation after stroke.Our objective is to highlight the clinical implications of CCS and we hope the differential diagnoses will be considered in patients with acute CNS diseases.展开更多
Transient stress-induced cardiomyopathies have been increasingly recognized and while rare,they tend to affect elderly women more than other demographic groups.One type,often called tako-tsubo cardiomyopathy （TTC）,i...Transient stress-induced cardiomyopathies have been increasingly recognized and while rare,they tend to affect elderly women more than other demographic groups.One type,often called tako-tsubo cardiomyopathy （TTC）,is typically triggered by significant emotional or physical stress and is associated with chest pain,electrocardiogram （ECG） changes and abnormal cardiac enzymes.Significant left ventricular regional wall motion abnormalities usually include an akinetic ＂ballooning＂ apex with normal or hyperdynamic function of the base.A second type,often called neurogenic stunned myocardium,typically associated with subarachnoid hemorrhage,also usually presents with ECG changes and positive enzymes,but the typical wall motion abnormalities seen include normal basal and apical left ventricular contraction with akinesis of the mid-cavity in a circumferential fashion.The pathophysiology,clinical care and typical courses,are reviewed.展开更多
文摘A comparative study was performed of the permeability of cell membranous structures in canine stunned myocardium and that of infarct myocardium by using colloidal lanthanum nitrate as an ultrastructure probe. Stunned myocardium was characterized by mitochondrial swelling, vacuolar formation, a few lanthanum granules deposrting inside cells and intact structure of such membranes as cell membrane, mitochondrial membrane and lysosome membrane.Infarct myocardium was characterized by a large number of lanthanum granules passing through ruptured cell membrane and depositing in the cytoplasm and mitochondria. These results suggest that membranous structure remained intact during the occurrence of stunned myocardium.
文摘Objective:To observe the effects of inhibition of glycolysis with iodoacetate (IAA) on calcium homeostasis and functional recovery of stunned myocardium in anesthetized dogs. Methods: Atomic absorption spectrophotometry was employed to measure myocyte calcium and magnesium contents. Hemodynamics were monitored with a multichannel electrophysiologic recorder. Results: In nonischemic canine hearts (control), IAA's inhibition of glycolysis failed to change the [Ca2+] and [Mg2+] levels and cardiac functional conditions, whereas in hearts subjected to 15-minute ischemia , [Ca2+] increased from nonischemic 1.40±0. 20μmol/g to ischemic 1.80±0.17 μmol/g (P<0. 05), while [Mg2+] decreased. After 30 min of reperfusion,[Ca2+] continued to increase from 1.57±0.21 μmol/g (nonischemic area)to 2. 26±0. 09 μmol/g (abnormal area) and 60 min of reperfusion saw a slight restoration (1.54±0. 16 μmol/g in nonischemic area and 2. 21±0.20 μmol/g in abnormal area). In the glycolysis-inhibiting group, the calcium level registered a significant rise after 30 min of reperfusion: 1.57±0.07 μmol/g in nonischemic area and 2. 90? 0.25 μmol/g in abnormal area (P<0. 01).There was a significant difference between the glycolysis-inhibiting group and the group to which IAA was not applied. [Mg2+] maintained at a relatively low level and registered a more remarkable drop during inhibition of glycolysis, P<0.01 in comparison with the non IAA-administered group,suggesting that inhibition of glycolysis could cause severe calcium overload to sustain, in addition to an obvious harm to cardiac function. Left ventricular end-diastolic pressure and diastolic factor T were augmented andp/dt(max)declined. Conclusion: Since in vivo inhibition of glycolysis seemed to lead to severe calcium overload and hemodynamics changes,it might indicate that glycolysis played an importent role in the restoration of calcium homeostasis in postischemic myocardium,and that ATP derived from glycolysis took a significant part in myocardial ion transport both at the stage of ischemia and the early stage of reperfusion and in cardiac functional recovery.
文摘This is a report of a study on the protective effect of berberine(Ber) on postischemic myocardial stunning and the role it plays in ATPase activity. Isolated working rat hearts were used with global ischemia for 30 min followed by reperfusing for 40 min. Both systolic and diastolic functions of stunned myocardium were significantly decreased. The recovery of LVSP×HR and CO was 52%±8% and 40%±8% respectively; LVEDP and T were elevated; while both Na +, K +ATPase activity and Ca 2+ , Mg 2+ ATPase activity of myocardial membrane and mitochondria were depressed. Berberine(25 mg·kg -1 ·d -1 , ip, 3 d, and 10 μmol L -1 for isolated heart perfusion) was able to enhance the percent recovery of LVSP×HR and CO to 85%±12% and 75%±11%, respectively, and reduce LVEDP from 298%±64% to 166%±44%, with an improvement in myocardial membrane Na +, K +ATPase activity and mitochondria Ca 2+ , Mg 2+ ATPase activity. This study suggested that berberine can protect cardiac function from ischemia reperfusion stunning injury by preserving ATPase activity in ischemic myocardium.
文摘BACKGROUND Cardiac injury may occur after acute pathology of central nervous system(CNS)without any evidence of primary cardiac diseases.The resulting structural and/or functional changes are called cerebrocardiac syndrome(CCS).The great majority of studies have been performed in patients with subarachnoid hemorrhage(SAH),while CCS data after intracerebral hemorrhage(ICH)are rare.It may cause diagnostic and therapeutic pitfalls for the clinician due to a lack of specific clinical manifestations and diagnostic methods.Understanding the underlying pathophysiological and molecular mechanism(s)following cerebrovascular incidents will help to implement prevention and treatment strategies to improve the prognosis.CASE SUMMARY A 37-year-old man with a history of hypertension presented to our department on an emergency basis because of a sudden dizziness and left limb weakness.Cerebral computed tomography(CT)suggested ICH in the occipital and parietal lobes,and the chosen emergency treatment was hematoma evacuation.Left ventricular(LV)dysfunction occurred after the next 48 h and the electrocardiogram(ECG)showed non-ST elevation myocardial infarction.CCS was suspected first in the context of ICH due to the negative result of the coronary CT angiogram.CONCLUSION Misinterpretation of ischemic-like ECGs may lead to unnecessary or hazardous interventions and cause undue delay of rehabilitation after stroke.Our objective is to highlight the clinical implications of CCS and we hope the differential diagnoses will be considered in patients with acute CNS diseases.
文摘Transient stress-induced cardiomyopathies have been increasingly recognized and while rare,they tend to affect elderly women more than other demographic groups.One type,often called tako-tsubo cardiomyopathy （TTC）,is typically triggered by significant emotional or physical stress and is associated with chest pain,electrocardiogram （ECG） changes and abnormal cardiac enzymes.Significant left ventricular regional wall motion abnormalities usually include an akinetic ＂ballooning＂ apex with normal or hyperdynamic function of the base.A second type,often called neurogenic stunned myocardium,typically associated with subarachnoid hemorrhage,also usually presents with ECG changes and positive enzymes,but the typical wall motion abnormalities seen include normal basal and apical left ventricular contraction with akinesis of the mid-cavity in a circumferential fashion.The pathophysiology,clinical care and typical courses,are reviewed.
