Transient Receptor Potential Vanilloid 2 Regulates Myocardial Response to Exercise

Abstract

The myocardial response to exercise is an adaptive mechanism that permits the heart to maintain cardiac output via improved cardiac function and development of hypertrophy. There are many overlapping mechanisms via which this occurs with calcium handling being a crucial component of this process. Our laboratory has previously found that the stretch sensitive TRPV2 channels are active regulators of calcium handling and cardiac function under baseline conditions based on our observations that TRPV2-KO mice have impaired cardiac function at baseline. The focus of this study was to determine the cardiac function of TRPV2-KO mice under exercise conditions. We measured skeletal muscle at baseline in WT and TRPV2-KO mice and subjected them to various exercise protocols and measured the cardiac response using echocardiography and molecular markers. Our results demonstrate that the TRPV2-KO mouse did not tolerate forced exercise although they became increasingly exercise tolerant with voluntary exercise. This occurs as the cardiac function deteriorates further with exercise. Thus, our conclusion is that TRPV2-KO mice have impaired cardiac functional response to exercise.

TRPV2 knockout mice demonstrate an improved cardiac performance following myocardial infarction due to attenuated activity of peri-infarct macrophages

“…Our data support previous reports regarding the mildly-attenuated cardiac performance in TRPV2-KO mice compared to their WT counterparts [ 15 , 16 ]. Moreover, Katanosaka and his colleagues have recently reported that heart-specific elimination of TRPV2 may be critically detrimental to cardiac structure and function in mice [ 29 ].…”

“…First, we wished to analyze whether TRPV2-WT and TRPV2-KO animals demonstrate any differences in cardiac function as previously suggested [ 15 , 16 ]. To this end, TRPV2-WT and KO male mice aged 12–16 weeks (6/arm) were studied by echocardiography.…”

Regulation of BECN1-mediated autophagy by HSPB6: Insights from a human HSPB6S10F mutant

“…M-mode measurements of the LV end diastolic dimension (LVEDD) and LV end systolic dimension (LVESD), posterior and anterior wall thickness and ejection time, measured at end diastole, were calculated from original tracings by employing a commercially available image analysis system (Freeland Medical, Alpharetta, GA, USA). 41…”

The Contractile Phenotype of Skeletal Muscle in TRPV1 Knockout Mice Is Gender-Specific and Exercise-Dependent

“…Although TRPV1 −/− mouse skeletal muscles have never been phenotyped before our investigation, other members of the TRPV family had. Naticchioni et al reported that the contractile function of skeletal muscles was unchanged in TRPV2 null mice [ 45 ]. Similarly, lack of TRPV4 did not cause any alteration of muscular force production or fatigue [ 46 ].…”