Changes in rhythmoinotropic reactions of the myocardium in chronic ischemia: Pathology or adaptation?

Афанасьев, С. А.; Bogomaz, Sergey A.; Alekseeva, E. D.; Chernyavskii, A. M.; Pekarskiĭ, V V

doi:10.1007/bf02444284

Cited by 5 publications

(8 citation statements)

References 3 publications

(1 reference statement)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The paradoxically high level of ATP in CMC of CHD patients indicates viability of these cells and preserves the ability to respond to various stimuli, for instance, to pharmacological agents. This assumption is based, first, on our data on inotropic capacity of the myocardium from CHD patients [2,3] and, second, on myocardial response to HC injections. Figure 1, a shows that the basal level of ATP in the myocardium of CHD patients treated with HC practically does not differ from that in relatively normal myocardium (patients with nonischemic pathology).…”

Section: Resultsmentioning

confidence: 99%

ATP-sparing effect of histochrome in acute myocardial ischemia in patients with coronary heart disease

1997

Self Cite

View full text Add to dashboard Cite

After in vitro ischemia, the content of adenosine triphosphate in myocardial bioptates from patients with heart diseases is reduced. This reduction is more pronounced in patients with coronary heart disease than in patients with rhythm disturbances. Administration of the antioxidant preparation histochrome to patients with coronary heart disease preserves ATP during ischemic exposure. Key Words: myocardium; ischemia; ATP; lipid peroxidation; antioxidantsSurgery, a radical treatment of coronary insufficiency in coronary heart disease (CHD), is associated with risk of some grave complications, especially in early postoperation period [1]. Apart from operation wound, these complications can be caused by reperfusion damage to the myocardium [8]. A prospective way of preventing this damage is the use of antioxidant preparations [5,9]. However, recent in vitro experiments have shown that ischemia-and reperfusioninduced disturbances of myocardial contractility, in particular, myocardial contracture are due not only to altered permeability of cell membranes, but also depend on the ATP pool remaining in cardiomyocytes (CMC) before reperfusion [12]. In light of this is was interesting to evaluate the effect of acute ischemia during heart surgery and antioxidant therapy on myocardial ATP content in CHD patients. MATERIALS AND METHODSExperiments were carried out on fragments from right auricle obtained during aortocoronary bypass The fragments were washed from blood with cooled physiological saline and cut into 2 portions: one was immediately frozen in liquid nitrogen, while the other was placed to a humidified chamber (20~ for 60 rain and then frozen in liquid nitrogen. The latter procedure adequately reproduces the conditions of aortocoronary bypass operation.Some patients with CHD (n=9) were prepared for operation according to routine scheme, while others (n=8) additionally received two intravenous injections of 3% histochrome (HC) in a dose of 1 mg/kg (24 h prior to operation and in the operating room). Histochrome, a novel Russian-manufactured antioxidant, was kindly provided by Dr. A. V. Lebedev (Russian Research and Manufacturing Cardio, logy Association). Fragments obtained from patients without CHD and operated for cardiac rhythm disturbances (n=6) served as the control.

show abstract

Section: Resultsmentioning

confidence: 99%

ATP-sparing effect of histochrome in acute myocardial ischemia in patients with coronary heart disease

1997

Self Cite

View full text Add to dashboard Cite

show abstract

“…The muscle tension was monitored throughout the adaptation period (60 min). After the end of adaptation, the final muscle tension was produced and contractive activity was recorded.The muscle contractive activity was assessed in the isometric mode by changes in the curves of tension and its first derivative [1,5]. A 6MKh1S mechanotron converter was used as an isometric sensor.…”

mentioning

confidence: 99%

“…The muscle contractive activity was assessed in the isometric mode by changes in the curves of tension and its first derivative [1,5]. A 6MKh1S mechanotron converter was used as an isometric sensor.…”

mentioning

confidence: 99%

Contribution of ?-adrenoceptors to the contractility of the human myocardium in chronic coronary heart disease

2005

View full text Add to dashboard Cite

Sympathetic regulation of the myocardium is mediated by a population of β -and α -adrenoceptors. Even the myocardium isolated from patients with chronic coronary insufficiency retains some basal adrenoceptor activity. A blockade of these receptors causes a negative inotropic effect [1]. Under the conditions of an α -adrenoceptor blockade, the effect of norepinephrine on the isolated myocardium of patients with chronic coronary heart disease (CHD) is augmented by a factor of 1.5 [1]. This finding is in good agreement with the fact that simultaneous stimulation of adrenoceptors is accompanied by mutual attenuation of their inotropic effects [2]. Conversely, a blockade of receptors of one type is equilibrated by an increased activity of receptors of the other type.Inotropic effects of the α -adrenoceptors are related to phosphoinositide metabolism, the products of which play the role of intracellular messengers. Therefore, α -adrenoceptor stimulation is one of the possible mechanisms of endogenous cardioprotection [3]. It is in this connection that Academician E.I. Chazov remarked, "Disturbance in the adrenergic regulation of the myocardium in chronic cardiac insufficiency is a topical problem" [4].The present study aims to investigate the capability of the α 1 -adrenoceptors for maintaining the contractile function of the myocardium in chronic coronary insufficiency.The study was performed on perfused myocardial strips isolated from biopsy material of the right atrial auricle. The excision of the right atrial auricle is obligatory during surgery conducted under the conditions of extracorporeal circulation. We investigated the myocardium in two groups of male patients. The test group included six patients with chronic CHD and angina of effort (functional classes III-IV according to the NYHA). These patients (mean age 50 ± 3 years) underwent aortocoronary bypass grafting. The control group included four patients with WPW syndrome (mean age 43 ± 2.4 years).Muscle strips were no less than 5 mm in length and no more than 1 mm 2 in section, had parallel fibers, and lacked a connective tissue membrane. The strips were perfused with Krebs-Henseleit solution saturated with carbogen (95% O 2 and 5% CO 2 ) in a thermally stabilized chamber (1 ml) at 36° C [1, 5].The frequency of muscle contractions was determined by rectangular-shaped electrical pulses with a 5-ms duration and an amplitude exceeding the excitation threshold by 20-30%. The pulses were transmitted through two massive silver electrodes located in the chamber. By means of a micromanipulator, the muscles were stretched out to achieve the maximum possible inotropic effect. The muscle tension was monitored throughout the adaptation period (60 min). After the end of adaptation, the final muscle tension was produced and contractive activity was recorded.The muscle contractive activity was assessed in the isometric mode by changes in the curves of tension and its first derivative [1,5]. A 6MKh1S mechanotron converter was used as an isometric sensor. The following param...

show abstract

“…Two-dimensional electrophoresis showed only acid HSP70 but no alkaline isoforms in coronary patients even with pronounced dyskinesia. Presumably, alkaline HSP70 isoforms are present in the myocardium directly involved in the dyskinesia zone.The formation of chronic coronary disease is paralleled by the development of hypoxemic injury in the myocardium and adaptation to these conditions [1,3,4]. Accumulation of stress proteins in cells is a manifestation of universal cellular reaction to extreme exposure in living organisms [6].…”

mentioning

confidence: 99%

“…The formation of chronic coronary disease is paralleled by the development of hypoxemic injury in the myocardium and adaptation to these conditions [1,3,4]. Accumulation of stress proteins in cells is a manifestation of universal cellular reaction to extreme exposure in living organisms [6].…”

mentioning

confidence: 99%

Initiation of stress protein synthesis in the myocardium of coronary patients

et al. 2004

View full text Add to dashboard Cite

We studied myocardial biopsy specimens from the right atrium of cardiological patients with different degree of cardiac ischemia obtained during surgery. No inducible HSP70 stress proteins were detected in atrial cardiomyocytes of patients with the WPW syndrome without signs of ischemic injuries of the heart. These proteins were detected in the myocardium of coronary patients. Their expression was more intense in patients with coronary disease paralleled by the development of myocardial dyskinesia. Two-dimensional electrophoresis showed only acid HSP70 but no alkaline isoforms in coronary patients even with pronounced dyskinesia. Presumably, alkaline HSP70 isoforms are present in the myocardium directly involved in the dyskinesia zone.

show abstract

Changes in rhythmoinotropic reactions of the myocardium in chronic ischemia: Pathology or adaptation?

Cited by 5 publications

References 3 publications

ATP-sparing effect of histochrome in acute myocardial ischemia in patients with coronary heart disease

ATP-sparing effect of histochrome in acute myocardial ischemia in patients with coronary heart disease

Contribution of ?-adrenoceptors to the contractility of the human myocardium in chronic coronary heart disease

Initiation of stress protein synthesis in the myocardium of coronary patients

Contact Info

Product

Resources

About