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Background and Purpose: Opioid analgesics can alleviate ischaemia/reperfusion (I/R) injury in chronic heart failure. However, the underlying mechanisms and targets remain unknown. Here, we investigate if caveolin‐3 (Cav3) interacts with μ opioid receptors and if Cav3–μ receptor interactions play a role in morphine‐induced cardioprotection in failing hearts. Experimental Approach: Cav3 and μ receptor proteins in human and rat heart tissue were determined by western blot, immunofluorescence and co‐immunoprecipitation. Methyl‐β‐cyclodextrin (MβCD), a destroyer of caveolae, and AAV‐Cav3 shRNA were used to reduce Cav3 expression in failing rat hearts. CTOP, a specific μ antagonist, was administrated before morphine preconditioning in perfused failing heart models of myocardial I/R injury. Key Results: Levels of Cav3 and μ receptor proteins were significantly higher in human and rat myocardial tissues with heart failure than in control tissues. Cav3 and μ receptor expression levels were positively correlated with disease severity. The signal of the cardiac Cav3 protein was colocalized with μ receptor in both the human and rat heart sections. Disruption of caveolae in the failing heart by either MβCD or AAV‐Cav3 shRNA significantly inhibits morphine‐induced phosphorylation of ERK1/2 and cardioprotection. Administration of CTOP substantially reduced Cav3 expression and morphine‐induced cardioprotective effect in heart failure. Conclusion and Implications: Our data suggest that up‐regulation of the Cav3/μ receptor complex is critical for morphine protection of the failing heart against I/R injury by regulating the ERK1/2 pathway. The activated Cav3/μ receptor complex is an understudied therapeutic target for opioid treatment of heart failure and ischaemic insult. [ABSTRACT FROM AUTHOR]

In this study, La15Fe2Ni72Mn7B2Al2 hydrogen storage was composited with grapheme and the effect of ball milling time on the microstructure and properties of the alloy were studied. XRD analysis shows that the as-milled composites alloy consists of LaNi5, La3Ni13B2 and (Fe, Ni) phases. No new phase is formed in the composites alloy with the milling time increases. The ball-milling treatment produced amorphous structure and refined the particle size of the alloy. Electrochemical studies revealed that the discharge capacity of composites alloy was significantly improved. The ball-milling process enhances the maximum discharge capacity and the dynamics performance, especially for the alloy with milling time of 30 min. Moreover, self-discharge behavior of the composites alloy were also increased by ball-milled. [ABSTRACT FROM AUTHOR]