Christoph A Blomeyer

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BACKGROUND Anesthetic and ischemic preconditioning share similar signal transduction pathways. The authors tested the hypothesis that the beta1-adrenergic signal transduction pathway mediates anesthetic and ischemic preconditioning in vivo. METHODS Pentobarbital-anesthetized (30 mg/kg) rabbits (n = 96) were instrumented for measurement of systemic(More)
Cardiac mitochondrial matrix (m) free Ca(2+) ([Ca(2+)]m) increases primarily by Ca(2+) uptake through the Ca(2+) uniporter (CU). Ca(2+) uptake via the CU is attenuated by extra-matrix (e) Mg(2+) ([Mg(2+)]e). How [Ca(2+)]m is dynamically modulated by interacting physiological levels of [Ca(2+)]e and [Mg(2+)]e and how this interaction alters bioenergetics are(More)
Remote ischemic preconditioning (remote IPC) elicits a protective cardiac phenotype against myocardial ischemic injury. The remote stimulus has been hypothesized to act on major signaling pathways; however, its molecular targets remain largely undefined. We hypothesized that remote IPC exerts its effects by activating the peroxisome-proliferator-activated(More)
BACKGROUND Anesthetic preconditioning is mediated by beta-adrenergic signaling. This study was designed to elucidate the role of beta-adrenergic signaling in desflurane-induced postconditioning. METHODS Pentobarbital-anesthetized New Zealand White rabbits were subjected to 30 min of coronary artery occlusion followed by 3 h of reperfusion and were(More)
OBJECTIVE An optimal administration protocol to induce a maximal effect of anesthetic preconditioning has not been evaluated to date. In this study, desflurane preconditioning was characterized with respect to its threshold, dose dependency, and continuous versus repetitive application. Furthermore, the role of beta(2)-adrenergic receptors in anesthetic(More)
BACKGROUND Ischemic preconditioning (IPC) and anesthetic-induced preconditioning against myocardial infarction are mediated via protein kinase B. Pim-1 kinase acts downstream of protein kinase B and was recently shown to regulate cardiomyocyte survival. The authors tested the hypothesis that IPC and anesthetic-induced preconditioning are mediated by Pim-1(More)
OBJECTIVES The authors tested the hypothesis that ischemic and desflurane-induced preconditioning are blocked by propofol. DESIGN A prospective, randomized, vehicle-controlled study. SETTING A university research laboratory. SUBJECTS New Zealand white rabbits (n = 52). METHODS Pentobarbital-anesthetized rabbits were subjected to 30 minutes of(More)
In cardiac mitochondria, matrix free Ca(2+) ([Ca(2+)]m) is primarily regulated by Ca(2+) uptake and release via the Ca(2+) uniporter (CU) and Na(+)/Ca(2+) exchanger (NCE) as well as by Ca(2+) buffering. Although experimental and computational studies on the CU and NCE dynamics exist, it is not well understood how matrix Ca(2+) buffering affects these(More)
The manner in which mitochondria take up and store Ca(2+) remains highly debated. Recent experimental and computational evidence has suggested the presence of at least two modes of Ca(2+) uptake and a complex Ca(2+) sequestration mechanism in mitochondria. But how Mg(2+) regulates these different modes of Ca(2+) uptake as well as mitochondrial Ca(2+)(More)
Under high Ca(2+) load conditions, Ca(2+) concentrations in the extra-mitochondrial and mitochondrial compartments do not display reciprocal dynamics. This is due to a paradoxical increase in the mitochondrial Ca(2+) buffering power as the Ca(2+) load increases. Here we develop and characterize a mechanism of the mitochondrial Ca(2+) sequestration system(More)
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