Beta-adrenergic preconditioning

Fig. 4.7 Infarct sizes of beta-adrenergic preconditioned hearts effects of 5-hydroxy-decanoate (1 x 10-4M) or adenosine deaminase (0.3U/ml) pretreatment. The drugs were given for 5 min before and during the administration of isoproterenol (lx 10-7 M).

PKC inhibitor polymyxin B. If this was true, one would expect beta-adrenergic preconditioning to share another characteristic of adenosine-mediated preconditioning, such as independence from activation of the mitochondrial Katp channel. Indeed, in our own laboratory, administration of 5-hydroxydecanoate (5-HD) did not have any effect on beta-adrenergic protection, supporting this notion (Figure 4.7) (unpublished observations). 

Beta-Adrenergic Preconditioning and Protection Against Apoptosis... 

On the whole, our experimental evidence suggests that beta-adrenergic preconditioning reduces both apoptosis and necrosis these events are associated with attenuated activation of p38 MAPK during ischemia and reperfusion. Whether this is the cause or the result of the cardioprotection remains to be established. 

Fig. 4.10 Effect of late beta-adrenergic preconditioning and L-NA pretreatment on infarct size. L-NA Na -nitro-L-arginme.

Late Preconditioning with Pharmacological Beta-Adrenergic Preconditioning... 

Moolman, J.A., Hartley, S., Van Wyk, J., Marais, E., and Lochner, A. 2006. Inhibition of myocardial apoptosis by ischaemic and beta-adrenergic preconditioning is dependent on p38 MAPK. Cardiovasc. Drugs Ther. 20 13-25. 

Beta-Adrenergic Involvement in Ischemic Preconditioning Catecholamine Release and Beta-Adrenergic Receptor Activation... 

Beta-Adrenergic Activation as Trigger in Ischemic and Pharmacologic Preconditioning... 

The question arose whether these observed changes in cAMP, and by implication, beta-adrenergic activation, played any role in the cardioprotection of ischemic preconditioning. Using the beta-1 adrenergic blocker alprenolol 7.5 x 10 5M during... 

The necessity of PKA activation for successful preconditioning is demonstrated by the following (i) the beta-adrenergic receptor blocker alprenolol partially abolished ischemic preconditioning (Lochner et al. 1999) (ii) landiolol, a short-acting beta-blocker, blunted the infarct size limitation induced by ischemic preconditioning (Sanada et al. 2004) (iii) PKA inhibitors such as H89 (Sanada et al. 2004 Inserte et al. 2004) and Rp-cAMPs (Sanada et al. 2004) blunted ischemic and dibutyryl-cAMP-induced preconditioning. 

Asimakis, G.K., Inners-McBride, K., Conti, V.R., and Yang, C.J. 1994. Transient beta adrenergic stimulation can precondition the rat heart against post-ischaemic contractile dysfunction. Cardiovasc. Res. 28 1726-1734. 

Lan, X., Wang, J., and Zhang, Y. 2005. Role of beta-adrenergic signal transduction pathway on myocardial ischemic preconditioning of rats. J. Huazhong Univ. Sci. Technol. Med. Sci. 25 709-711. 

Lochner, A., Genade, S., Tromp, E., Podzuweit, T., and Moolman, J.A. 1999. Ischemic preconditioning and the beta-adrenergic signal transduction pathway. Circulation. 100 958-966. 

Yabe, K., Ishishita, H., Tanonaka, K., and Takeo, S. 1998. Pharmacologic preconditioning induced by beta-adrenergic stimulation is mediated by activation of protein kinase C. J. Cardiovasc. Pharmacol. 32 962-968. 

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