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Anesth Analg 2003;97:1025-1032
© 2003 International Anesthesia Research Society

ANESTHETIC PHARMACOLOGY

Intracellular Mechanism of Mitochondrial Adenosine Triphosphate-Sensitive Potassium Channel Activation with Isoflurane

Yuri Nakae, MD PhD*, Shinji Kohro, MD PhD*, Quinn H. Hogan, MD*, and Zeljko J. Bosnjak, PhD*,{dagger}

Departments of *Anesthesiology and {dagger}Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin

Address correspondence and reprint requests to Quinn H. Hogan, MD, Department of Anesthesiology, Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI 53226. Address e-mail to qhogan{at}mcw.edu


   Abstract
Top
 Abstract
Introduction
 Methods
 Results
 Discussion
 References
 
The precise mechanism of isoflurane and mitochondrial adenosine triphosphate-sensitive potassium channel (mitoKATP) interaction is still unclear, although the mitoKATP is involved in isoflurane-induced preconditioning. We examined the role of various intracellular signaling systems in mitoKATP activation with isoflurane. Mitochondrial flavoprotein fluorescence (MFF) was measured to quantify mitoKATP activity in guinea pig cardiomyocytes. To confirm isoflurane-induced MFF, cells were exposed to Tyrode’s solution containing either isoflurane (1.0 ± 0.1 mM) or diazoxide and then both drugs together (n = 10 each). In other studies, the following drugs were each added during isoflurane administration: adenosine or the adenosine receptor antagonist 8-(p-sulfophenyl)-theophylline (SPT); the protein kinase C (PKC) activators phorbol-12-myristate-13-acetate (PMA) and phorbol-12,13-dibutyrate (PDBu); the PKC inhibitors polymyxin B and staurosporine; the tyrosine kinase inhibitor lavendustin A; or the mitogen-activated protein kinase inhibitor SB203580 (n = 10 each). Isoflurane potentiated MFF induced by diazoxide (100 µM), and diazoxide also increased isoflurane-induced MFF. PMA (0.2 µM), PDBu (1 µM), and adenosine (100 µM) induced MFF. However, SPT (100 µM), polymyxin B (50 µM), staurosporine (200 nM), lavendustin A (0.5 µM), and SB203580 (10 µM) all failed to inhibit the effect of isoflurane. Our results show that isoflurane, adenosine, and PKC activate mitoKATP. However, our data do not support an action of isoflurane through pathways involving adenosine, PKC, tyrosine kinase, or mitogen-activated protein kinase. These results suggest that isoflurane may directly activate mitoKATP.

IMPLICATIONS: Our results show that isoflurane activates mitochondrial adenosine triphosphate-sensitive potassium (mitoKATP) channels, but not through pathways involving adenosine, protein kinase C, tyrosine kinase, or p38 mitogen-activated protein kinase. Isoflurane may directly activate mitoKATP channels.


   Introduction
Top
 Abstract
 Introduction
Methods
 Results
 Discussion
 References
 
Ischemic preconditioning is a phenomenon whereby exposure of the myocardium to a brief episode of ischemia and reperfusion markedly reduces tissue necrosis induced by subsequent prolonged ischemia. A variety of intracellular signaling pathways have been implicated in the protective mechanism of ischemic preconditioning. Current evidence indicates that mitochondrial adenosine triphosphate (ATP)-sensitive potassium (mitoKATP) channels serve as one of the effectors of cardioprotection and that adenosine receptor activation primes the opening of mitoKATP channels in a protein kinase C (PKC)-dependent manner (1,2). In addition, tyrosine kinase and p38 mitogen-activated protein (MAP) kinase may provide pathways downstream of PKC, depending on the animal species and preconditioning protocols (3,4).

Isoflurane has a cardioprotective effect that mimics the ischemic preconditioning phenomenon. Experimental evidence suggests that the cardioprotective effect of isoflurane is mediated through adenosine receptors and ATP-sensitive potassium (KATP) channels in rabbits and dogs (5,6). More current evidence indicates that PKC and the mitoKATP channel are involved in isoflurane-induced preconditioning (7,8). However, the precise mechanism of isoflurane and mitoKATP channel interaction is still unclear. We have previously reported that isoflurane induces mitochondrial flavoprotein fluorescence (MFF), an index of mitoKATP channel activation, in guinea pig ventricular myocytes (9). Accordingly, we tested whether the mitoKATP channel activation induced by isoflurane is mediated through adenosine receptors, PKC, and pathways downstream of PKC that include tyrosine kinase or MAP kinase.


   Methods
Top
 Abstract
 Introduction
 Methods
Results
 Discussion
 References
 
This study was conducted according to US National Institutes of Health standards (National Institutes of Health Publication 95-23, revised 1996) and was approved by the Institutional Animal Use and Care Committee. Single cardiac myocytes were isolated from ventricles of the guinea pigs weighing 200–250 g. The guinea pig was injected intraperitoneally with 1000 U of heparin and sodium pentobarbital (70 mg/kg). During deep anesthesia, the thoracic cavity was opened, and the heart was quickly excised. The heart was then mounted on a Langendorff apparatus and perfused in retrograde fashion via the aorta with an oxygenated buffer solution containing Joklik’s minimum essential medium. After blood was cleared from the heart, it was perfused for approximately 14 min in an enzyme solution containing Joklik’s medium, collagenase (Type II) 0.4 mg/mL, protease (Type XIV) 0.17 mg/mL, and bovine albumin fraction V 1 mg/mL (pH 7.23). The dispersed cells were filtered, centrifuged, and washed in a recovery solution containing Joklik’s medium, 1 mM CaCl2, and 1 g/100 mL bovine albumin fraction V. Additional washing in Tyrode’s solution (mM; NaCl 132, KCl 4.8, MgCl2 1.2, HEPES 10.0, glucose 5.0, and CaCl2 1.0) was performed before the cells were ready for experiments. The cells were stored in Tyrode’s solution at room temperature (22°C–23°C). Only rod-shaped cells with clear borders and striations were selected for experiments, and they were used within 8 h of isolation.

Because of the effect on mitochondrial redox state, mitoKATP currents may be indirectly measured by fluorescent determination of flavoprotein oxidation, a flavin adenine dinucleotide (FAD)-linked enzyme. Cells were superfused with a modified glucose-free Tyrode’s solution containing 140 mM NaCl, 5 mM KCl, 1 mM MgCl2, 10 mM HEPES, and 2 mM CaCl2 (adjusted to pH 7.4 with NaOH). Autofluorescence of FAD-linked enzymes (MFF) in the mitochondria was excited every 30 s with light from a xenon laser bandpass-filtered to 488 ± 20 nm. Emitted fluorescence was passed through 515-nm long-pass filter, and the relative fluorescence was averaged during the excitation. Fluorescence images were obtained with 40x oil-immersion objective lenses on an inverted fluorescence microscope (Diaphot; Nikon, Huntley, IL) with an Odyssey confocal scanning attachment (Noran, Middleton, WI). The values of fluorescence intensity were expressed as arbitrary units (range, 0–255; MetaMorph Version 2; Universal Imaging, West Chester, PA). The stable mean fluorescence intensities were obtained by averaging five sequential images. All recordings were performed at room temperature (22°C–23°C). At the end of each protocol, MFF was calibrated with 2,4-dinitrophenol (DNP; 100 µM), an uncoupler of oxidative phosphorylation that releases protons in the mitochondrial matrix and thus produces maximal oxidation, and with cyanide (CN; 4 mM), which blocks mitochondrial respiration distally at the level of cytochrome c oxidase and produces minimal oxidation. The data were expressed as percentages of the differences between DNP- and CN-exposure values.

After stabilization in Tyrode’s solution (control) for 10 min, cells were exposed to Tyrode’s solution containing either isoflurane or diazoxide (1) (mitoKATP channel opener; 100 µM) for 10 min and then to both drugs together for 15 min (n = 10 each) (Fig. 1A). Every 30 s, an image was taken and average fluorescence intensity was calculated. The peak effect was recorded.



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  		Figure 1. Experimental protocols. Baseline indicates a period of no experimental intervention. In all studies, the fluorescence level was calibrated by 2,4-dinitrophenol (DNP) and cyanide (CN) at the end of each protocol. ISO = isoflurane; PKC = protein kinase C; MAP = mitogen-activated protein.

 
After stabilization with Tyrode’s solution (control) for 10 min, myocytes were exposed to Tyrode’s solution containing either isoflurane or adenosine (2) (100 µM) for 10 min and then to isoflurane plus adenosine for 15 min (n = 10 each) (Fig. 1B). In other cells, after stabilization with Tyrode’s solution (control) for 10 min, myocytes were exposed to Tyrode’s solution containing the adenosine receptor antagonist 8-(p-sulfophenyl)-theophylline (2) (SPT; 100 µM) for 10 min and then to isoflurane plus SPT for 15 min (n = 10 each). As described previously, an image was taken and the average fluorescence intensity was calculated.

After stabilization with Tyrode’s solution (control) for 10 min, myocytes were exposed to Tyrode’s solution containing drug for 10 min and then to Tyrode’s solution containing isoflurane with drug for 15 min (Fig. 1C). The drugs tested were the PKC activators phorbol-12-myristate-13-acetate (10) (PMA; 0.2 µM) and phorbol-12,13-dibutyrate (11) (PDBu; 1 µM) and the PKC inhibitors polymyxin B (2) (50 µM) and staurosporine (12) (200 nM; n = 10 for each drug). As described previously, an image was taken and the average fluorescence intensity was calculated.

After stabilization with Tyrode’s solution (control) for 10 min, myocytes were exposed to Tyrode’s solution containing either the tyrosine kinase inhibitor lavendustin A (3) (0.5 µM) or the p38 MAP kinase inhibitor SB203580 (4) (10 µM) for 10 min and then to Tyrode’s solution containing isoflurane with each drug for 15 min (n = 10 for each drug) (Fig. 1D). As described previously, an image was taken and the average fluorescence intensity was calculated.

The following drugs and chemicals were used in this study: pentobarbital and isoflurane (Abbott Laboratories, Chicago, IL); heparin sodium injection (Elkins-Sinn, Cherry Hill, NJ); Joklik’s modified minimum essential medium and type II collagenase (GIBCO, Life Technologies, Gaithersburg, MD); bovine albumin fraction V (Serologicals, Milwaukee, WI); protease, adenosine, diazoxide, DNP, and CN (Sigma-Aldrich, St. Louis, MO); and PMA, PDBu, polymyxin B, staurosporine, lavendustin A, and SB203580 (Research Biochemicals, La Jolla, CA). Adenosine, diazoxide, PMA, PDBu, staurosporine, lavendustin A, and SB203580 were dissolved in dimethyl sulfoxide before they were added into experimental solution. The final concentration of dimethyl sulfoxide was <0.1%. Dimethyl sulfoxide (0.1%) did not show any effect on MFF (data not shown). Isoflurane was dissolved in experimental solution, and concentrations of isoflurane were adjusted to 1.0 ± 0.1 mM in each protocol. The concentrations in the recording chamber were measured by gas chromatography (GC-8A; Shimazu, Columbia, MO).

Data are presented as mean ± SD. The data within multiple groups were analyzed by analysis of variance for repeated measures followed by a Duncan multiple range test. A value of P < 0.05 was considered significant.


   Results
Top
 Abstract
 Introduction
 Methods
 Results
Discussion
 References
 
Three to five guinea pigs were used for this protocol and subsequent protocols. Isoflurane increased MFF (12% ± 4% vs 32% ± 13%, control versus isoflurane; n = 10; P < 0.05), and diazoxide enhanced isoflurane-induced MFF (32% ± 13% vs 51% ± 20%, isoflurane versus isoflurane plus diazoxide; P < 0.05; Fig. 2, A and C). Diazoxide alone also increased MFF (6% ± 4% vs 22% ± 14%, control versus diazoxide; n = 10; P < 0.05), and isoflurane potentiated MFF induced by diazoxide (22% ± 14% vs 35% ± 12%, diazoxide versus diazoxide plus isoflurane; P < 0.05; Fig. 2, B and D). These findings confirm that, similar to previous findings (9), the cells in this study are responsive to diazoxide and isoflurane. Because their responses are additive, the dose of isoflurane does not produce a saturating effect on MFF.



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  		Figure 2. A and B, Effects of isoflurane (ISO) and diazoxide (DIAZO) on mitochondrial flavoprotein fluorescence (MFF): time course of MFF in cells exposed to either DIAZO (100 µM) or ISO (1.0 ± 0.1 mM) and to both drugs together. MFF was calibrated by exposing cells to 2,4-dinitrophenol (DNP) (100 µM) and cyanide (CN) (4 mM) at the end of the experiments. C, DIAZO enhanced ISO-induced MFF; *P < 0.05 versus control; #P < 0.05 versus the ISO group. D, ISO potentiated DIAZO-induced MFF; *P < 0.05 versus control; {dagger}P < 0.05 versus the DIAZO group.

 
Adenosine increased isoflurane-induced MFF (20% ± 6% vs 29% ± 12%, isoflurane versus isoflurane plus adenosine; n = 10; P < 0.05; Fig. 3A). Isoflurane also potentiated MFF induced by adenosine (13% ± 5% vs 25% ± 7%, adenosine versus adenosine plus isoflurane; n = 10; P < 0.05; Fig. 3B). Isoflurane caused an increase in MFF in the presence of SPT (5% ± 3% vs 17% ± 11%, control versus SPT plus isoflurane; n = 10; P < 0.05; Fig. 3C), whereas SPT alone did not have any effect on MFF.



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  		Figure 3. Effects of isoflurane (ISO) and adenosine (ADO) on mitochondrial flavoprotein fluorescence (MFF). A, ADO increased the ISO-induced MFF; *P < 0.05 versus control; #P < 0.05 versus the ISO group. B, ISO potentiated the ADO-induced MFF; *P < 0.05 versus control; *P < 0.05 versus the ADO group. C, Effects of ISO on MFF in the presence of 8-(p-sulfophenyl) theophylline (SPT). SPT did not inhibit the ISO-induced MFF. *P < 0.05 versus control.

 
PMA and PDBu alone increased MFF (5% ± 3% vs 17% ± 14%, control versus PMA; 9% ± 4% vs 21% ± 9%, control versus PDBu; n = 10 each; P < 0.05; Fig. 4, A and B). Because PKC activation stimulates MFF, we examined whether isoflurane acts through this pathway. Isoflurane did not potentiate MFF induced by PMA and PDBu. Isoflurane caused an increase in MFF in the presence of polymyxin B and staurosporine (6% ± 4% vs 21% ± 4%, control versus polymyxin B plus isoflurane; 6% ± 6% vs 24% ± 11%, control versus staurosporine plus isoflurane; n = 10 each; P < 0.05; Fig. 5, A and B). Neither polymyxin B nor staurosporine alone had any effects on MFF.



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  		Figure 4. Effects of isoflurane (ISO) on mitochondrial flavoprotein fluorescence (MFF) in the presence of phorbol-12 myristate-13-acetate (PMA) (A) and phorbol-12,13-dibutyrate (PDBu) (B). ISO did not enhance the PMA- and PDBu-induced MFF. *P < 0.05 versus control.

 


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  		Figure 5. Effects of isoflurane (ISO) on mitochondrial flavoprotein fluorescence (MFF) in the presence of polymyxin B (PMB) (A) and staurosporine (STA) (B). PMB and STA did not inhibit ISO-induced MFF. *P < 0.05 versus control; #P < 0.05 versus PMA; {dagger}P < 0.05 versus STA.

 
Neither lavendustin A nor SB203580 inhibited isoflurane-induced MFF (5% ± 5% vs 19% ± 9%, control versus lavendustin A plus isoflurane; 6% ± 8% vs 20% ± 15%, control versus SB203580 plus isoflurane; n = 10 each; P < 0.05; Fig. 6, A and B). Lavendustin A and SB203580 alone did not have any effect on MFF.



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  		Figure 6. Effects of isoflurane (ISO) on mitochondrial flavoprotein fluorescence (MFF) in the presence of lavendustin A (LAV) and SB203580 (SB). LAV and SB did not inhibit ISO-induced MFF. *P < 0.05 versus control; #P < 0.05 versus LAV; {dagger}P < 0.05 versus SB.

 

   Discussion
Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
References
 
Considerable evidence suggests that mitoKATP channels may serve as effectors of cardioprotection. Diazoxide protects hearts from ischemia/reperfusion injury (13), and 5-hydroxydecanoate (5-HD), a specific inhibitor of the mitoKATP channel, inhibits the protection afforded by diazoxide. Anesthetic-induced preconditioning seems to share some of the common mechanisms with ischemic preconditioning. Protective effects of isoflurane are abolished by the KATP channel blockers 5-HD and glyburide, suggesting that this protection is, in part, mediated by mitoKATP channels (6,8). Our previous work has shown that isoflurane-induced MFF is also blocked by 5-HD (9), indicating that this response is due to an action of isoflurane on mitoKATP channels. This study confirms that isoflurane activates mitoKATP channels, as indicated by the mitochondrial flavoprotein oxidation similar to and additive to that produced by diazoxide. This finding is consistent with the possibility that mitoKATP channels play a critical role in volatile anesthetic-mediated cardiac preconditioning.

Activation of mitoKATP channels has been linked to preconditioning by a pathway involving adenosine receptors. Adenosine receptor activation primes the opening of mitoKATP channels in isolated rabbit cardiomyocytes (2), and adenosine in this study increased MFF, an index of mitoKATP channel opening. Isoflurane-induced cardioprotection and preconditioning in intact animals is partially attenuated by a selective A1 receptor antagonist (8-cyclopentyl-1,3,dipropyl-xanthine) (5) and is eliminated by SPT pretreatment (6). However, our data show that SPT does not inhibit isoflurane-induced MFF. This finding indicates that mitoKATP channel activation by isoflurane may not be mediated via the adenosine receptor, but rather that isoflurane may activate mitoKATP channels directly. Han et al. (14) demonstrated that isoflurane diminishes the ATP sensitivity of sarcolemmal KATP channels in rabbit ventricular myocytes and that isoflurane directly interacts with the ATP-binding site of the channel to increase the probability of KATP channel opening. Our preliminary study of mitoKATP channels reconstituted in the lipid bilayers similarly supports a direct action of isoflurane (15). Our experiments with sequential drug administration also show that isoflurane may act on mitoKATP channels without interfering with the adenosine pathway of channel activation.

Although we have demonstrated that PKC itself increases MFF, it is also evident that the action of isoflurane on mitoKATP channels is not through this intracellular signaling pathway in guinea pig ventricular myocytes. PKC is one of the important downstream steps after adenosine receptor activation. PKC activators are just as protective as ischemic preconditioning (12), and preconditioning can be blocked by a variety of PKC inhibitors, including polymyxin B and staurosporine. Volatile anesthetics can prime mitoKATP channels in rat myocytes through multiple triggering PKC-coupled signaling pathways (16). Also, the highly selective PKC inhibitor chelerythrine abolishes cardioprotection in rats (12). In a study of patients during cardiac surgery, PKC was implicated as a critical mediator of the cardioprotective response to isoflurane (17). However, Toller et al. (7) showed that a large dose of the PKC inhibitor bisindolylmaleimide produced no cardioprotective effects on the recovery of stunned myocardium in dogs.

There are differences in animal species, experimental methods, and drugs used between previous studies and this study. Responses to staurosporine and polymyxin B are different compared with those from previous studies that evaluated the role of PKC during myocardial ischemia, because these drugs may also inhibit cyclic adenosine monophosphate-dependent protein kinase, myosin light chain kinase, and tyrosine kinase (18). Although chelerythrine and bisindolylmaleimide are reported to be more selective PKC inhibitors, these drugs enhanced the emitted fluorescence signal nonspecifically (data not shown). Other findings from our laboratory also suggest a complex involvement of PKC in modulating the isoflurane effect on the sarcolemmal KATP channels (19). Isoflurane alone was unable to elicit sarcolemmal KATP channel opening; however, it could facilitate the further opening of the channel after initial channel activation by pinacidil. The isoflurane effect on the KATP channel required an intracellular component, likely including the translocation of the specific PKC isoforms (11). In this study, polymyxin B and staurosporine were chosen to inhibit endogenous PKC. Although it is now generally accepted that PKC isozyme translocation occurs during preconditioning, the effect may be selective for certain PKC isozymes without a demonstrable change in total PKC activity. In light of this, clarification of our findings on PKC will require examination of specific PKC isozymes.

Tyrosine kinase and MAP kinase can participate in pathways downstream from PKC activation. At larger concentrations (0.5 µM), lavendustin A inhibits nonreceptor tyrosine kinase and completely blocks the reduction in infarct size elicited by preconditioning (3). However, the effect of p38 MAP kinase on preconditioning depends on animal species and experimental protocols. The selective inhibitor of p38 MAP kinase, SB203580, is able to abort protection triggered by ischemic preconditioning in isolated rabbit cardiomyocytes (4). In contrast, another group reported that SB203580 promotes injury in nonpreconditioned cells (20). There has been minimal examination of the roles of tyrosine kinase and MAP kinase on anesthetic-induced preconditioning. Some preliminary data on sarcolemmal KATP channels indicate that basal protein tyrosine kinase activity exerts inhibitory control over the channel via tyrosine residue phosphorylation (21). This study shows that tyrosine kinase and p38 MAP kinase do not have any effect on mitoKATP channel activation by isoflurane in isolated guinea pig cardiomyocytes.

The mitochondrial redox state can be monitored by recording the fluorescence of FAD-linked enzymes in the mitochondria (1). Opening of mitoKATP channels dissipates the inner mitochondrial membrane potential established by the proton pump. This dissipation accelerates electron transfer by the respiratory chain and, if uncompensated by increased production of electron donors (such as nicotinamide adenine dinucleotide), leads to net oxidation of the mitochondria. Our finding that diazoxide produced a reversible oxidation of the flavoproteins agrees with those (1,10) who have argued that oxidation results from an uncoupling effect of mitoKATP channel opening. Others, however, have shown that flavoprotein oxidation, as indicated by increased autofluorescence, is not detected in response to diazoxide (22). There are differences in the metabolic state of the cells and in experimental conditions between their study and this study. They used freshly isolated myocytes in physiological saline and worked at 32°C, whereas we used freshly isolated myocytes in glucose-free solution at room temperature. In this context, future studies will be required to define the exact relationship between mitoKATP channel opening and MFF under different experimental conditions, such as temperature. Furthermore, there are a few exceptions in which MFF fails to reflect the mitoKATP channel activation. DNP, which is used to calibrate MFF, has been reported to increase electron flow through the respiratory chain, produce the net oxidation of the mitochondrial matrix, and increase MFF. In addition, it is difficult to assess the effect of the KATP channel inhibitor glibenclamide on MFF; glibenclamide independently increases MFF because of a primary uncoupling effect (23).

It still remains unclear how the opening of mitoKATP channels might protect against ischemic damage. Mitochondrial depolarization accelerates respiration, slows ATP production, releases accumulated Ca2+, produces swelling, and stimulates the efflux of intermembrane proteins (24). However, a conflicting report claims that the opening of mitoKATP channels has little effect on respiration, membrane potential, or Ca2+ uptake but does have an important effect on matrix and intermembrane space volume (25). Those authors also demonstrated that uncoupling and depolarization secondary to opening mitoKATP channels in vivo are too small to cause significant direct effects on mitochondrial energetics. Another possibility is that mitochondrial depolarization secondary to opening mitoKATP channels protects the heart by reducing mitochondrial Ca2+ uptake. In this fashion, inhibition of the mitochondrial Ca2+ uniporter by ruthenium red protects the hearts against ischemia and reperfusion injury (26).

In conclusion, our results show that multiple signaling cascades may activate mitoKATP channels. However, isoflurane does not act through pathways that involve adenosine, PKC, tyrosine kinase, or MAP kinase. This suggests that isoflurane may activate mitoKATP channels directly.


   Acknowledgments
 
Supported in part by US Public Health Service Grants HL 34708 and GM66730 (ZJB) and the Department of Anesthesiology, Sapporo Medical University, Sapporo, Japan.


   References
Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 

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Accepted for publication April 30, 2003.




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M. L. Riess, A. D. Costa, R. Carlson Jr, K. D. Garlid, A. Heinen, and D. F. Stowe
Differential Increase of Mitochondrial Matrix Volume by Sevoflurane in Isolated Cardiac Mitochondria
Anesth. Analg., April 1, 2008; 106(4): 1049 - 1055.
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J. A. Symons and P. S. Myles
Myocardial protection with volatile anaesthetic agents during coronary artery bypass surgery: a meta-analysis
Br. J. Anaesth., August 1, 2006; 97(2): 127 - 136.
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M. J. M. de Klaver, G. S. Weingart, T. G. Obrig, and G. F. Rich
Local anesthetic-induced protection against lipopolysaccharide-induced injury in endothelial cells: the role of mitochondrial adenosine triphosphate-sensitive potassium channels.
Anesth. Analg., April 1, 2006; 102(4): 1108 - 1113.
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S. Kohro, Q. H. Hogan, D. C. Warltier, and Z. J. Bosnjak
Protein Kinase C Inhibitors Produce Mitochondrial Flavoprotein Oxidation in Cardiac Myocytes
Anesth. Analg., November 1, 2004; 99(5): 1316 - 1322.
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Lippincott, Williams & Wilkins Anesthesia & Analgesia® is published for the International Anesthesia Research Society® by Lippincott Williams & Wilkins with the assistance of Stanford University Libraries' HighWire Press®. Copyright 2006 by the International Anesthesia Research Society. Online ISSN: 1526-7598   Print ISSN: 0003-2999 HighWire Press