Pharmacologic preconditioning by delta-opioid agonists occurs via activation of an adenosine triphosphate (ATP)-gated potassium channel (I(KATP)). Opening of mitochondrial I(KATP) confers pharmacologic preconditioning whereas opening the sarcolemmal I(KATP) shortens action potential duration and is proarrhythmic. This study investigated whether SNC-80, a selective delta-opioid agonist, is associated with development of ventricular arrhythmia due to activation of I(KATP). Rabbit isolated hearts were subjected to 12 min of hypoxia and 40 min of reoxygenation after pretreatment with SNC-80 (1 microM, n = 6), pinacidil (1.25 microM, n = 12), or BMS-191095 (6.0 microM, n = 4). Nine additional hearts served as controls. The cytoprotective effects of SNC-80 at a concentration of 1 microM were confirmed using 30 min of regional ischemia followed by 120 min of reperfusion. Ventricular fibrillation (VF) developed in 11 of 12 pinacidil-treated hearts whereas none of the SNC-80-treated (zero of six) hearts developed VF (P < 0.001 compared with pinacidil pretreatment) and zero of four BMS-191095-pretreated hearts developed VF. Similarly, zero of nine control hearts developed VF. SNC-80 reduced infarct size expressed as a percentage of the area at risk from 33 +/- 4% to 14 +/- 3% (P = 0.004) compared with control. SNC-80, which selectively activates the delta-opioid receptor, provided cytoprotection but did not induce VF after hypoxia reoxygenation. The results indicate that pinacidil-induced nonselective activation of I(KATP) results in proarrhythmia that is dependent on activation of the sarcolemmal I(KATP). Selectivity for the mitochondrial I(KATP) is necessary to prevent induction of a proarrhythmic state.
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http://dx.doi.org/10.1097/00005344-200305000-00011 | DOI Listing |
J Cardiothorac Surg
January 2025
Department of Cardiology, Fujian Medical University Union Hospital, Fujian Heart Medical Center, Fujian Institute of Coronary Heart Disease, Fujian Clinical Medical Research Center for Heart and Macrovascular Disease, Fuzhou, 350001, China.
Objective: The objective of this study is to assess the predictive utility of perioperative P-wave parameters in patients with paroxysmal atrial fibrillation (PAF) undergoing catheter ablation, and to develop a predictive model using these parameters.
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Diabetol Metab Syndr
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Department of Endocrinology, Bharti Hospital, Karnal, Haryana, India.
Background: Of the numerous complications encountered by people with diabetes (PWD), the effect on mental health is concerning. Within mental health, diabetes distress (DD) occurs when a patient has unfavourable emotional stress while managing their condition, which can be managed by coping strategies but are less studied together in Indian settings. So, the present study aimed to determine the proportion of DD and associated factors and coping skills among the PWD.
View Article and Find Full Text PDFLipids Health Dis
January 2025
Department of Cardiology, West China Hospital, Sichuan University West China School of Medicine, 37 Guoxue Road, Chengdu, Sichuan, 610041, China.
Background: Atrial fibrillation (AF) is the most prevalent arrhythmia encountered in clinical practice. Triglyceride glucose index (Tyg), a convenient evaluation variable for insulin resistance, has shown associations with adverse cardiovascular outcomes. However, studies on the Tyg index's predictive value for adverse prognosis in patients with AF without diabetes are lacking.
View Article and Find Full Text PDFInt J Obes (Lond)
January 2025
Department of Cardiology, Sakakibara Heart Institute, Tokyo, Japan.
Background: Obesity is a risk factor for heart failure (HF) development but is associated with a lower incidence of mortality in HF patients. This obesity paradox may be confounded by unrecognized comorbidities, including cachexia.
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J Cardiovasc Transl Res
January 2025
Cardiac Regeneration and Ageing Lab, Institute of Geriatrics (Shanghai University), Affiliated Nantong Hospital of Shanghai University (The Sixth People's Hospital of Nantong), School of Medicine, Shanghai University, Nantong, 226011, China.
HFpEF is a prevalent and complex type of heart failure. The concurrent presence of conditions such as obesity, hypertension, hyperglycemia, and hyperlipidemia significantly increase the risk of developing HFpEF. Mitochondria, often referred to as the powerhouses of the cell, are crucial in maintaining cellular functions, including ATP production, intracellular Ca regulation, reactive oxygen species generation and clearance, and the regulation of apoptosis.
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