Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026850 (muscular dystrophy)
 5,870 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The stretch-induced increase in force production of ventricular muscle is biphasic. An abrupt increase in force coincides with the stretch, which is then followed by a slower response that develops over minutes (the slow force response or SFR). The SFR is accompanied by a slow increase in the magnitude of the intracellular Ca2+ transient, but the stretch-dependent mechanisms that give rise to this remain controversial. We characterized the SFR using right ventricular trabeculae from mouse hearts. Application of three different blockers of stretch-activated non-selective cation channels (SAC NSC) reduced the magnitude of the SFR 60s after stretch (400 microM streptomycin: from 86+/-25% to 38+/-14%, P<0.01, n=9; 10 microM GdCl3: from 65+/-21%, to 12+/-7%, P<0.01, n=7; 10 microM GsMTx-4 from 122+/-40% to 15+/-8%, P<0.05, n=6). Streptomycin also decreased the increase in Ca2+ transient amplitude 60s after the stretch from 43.5+/-12.7% to 5.7+/-3.5% (P<0.05, n=4), and reduced the stretch-dependent increase in intracellular Ca2+ in quiescent muscles when stretched. The transient receptor potential, canonical channels TRPC1 and TRPC6 are mechano-sensitive, non-selective cation channels. They are expressed in mouse ventricular muscle, and could therefore be responsible for stretch-dependent influx of Na+ and/or Ca2+ during the SFR. Expression of TRPC1 was investigated in the mdx heart, a mouse model of Duchenne's muscular dystrophy. Resting Ca2+ was raised in isolated myocytes from old mdx animals, which was blocked by application of SAC blockers. Expression of TRPC1 was increased in the older mdx animals, which have developed a dilated cardiomyopathy, and might therefore contribute to the dilated cardiomyopathy.
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PMID:Stretch-activated channels in the heart: contributions to length-dependence and to cardiomyopathy. 1836 38

Transient receptor potential (TRP) channels are expressed in almost every human tissue, including the heart and vasculature. Most are permeable to Ca(2+) and play unique roles as multifunctional cellular sensors. Their involvement in many fundamental cell functions (eg, contraction, proliferation, and cell death) has made investigating their roles in human disease an urgent priority for medical science. This review presents an overview of current knowledge about the pathological role of TRP channels in heart disease and highlights some TRP channels with anticipated roles in disease. Evidence suggests that (a) upregulation of TRPC channels is involved in the development of cardiac hypertrophy and heart failure; (b) TRPC1, TRPC6, and TRPV2 play a role in the pathogenesis of cardiomyopathy associated with muscular dystrophy; (c) TRPC6 or TRPM4 is involved in the delayed after-depolarization; (d) TRPP2 is involved in the normal development of the interventricular and interatrial septa; and (e) neuronal TRPV1 acts as a detector of pain-producing stimuli. Ultimately, TRP channels might become novel pharmacological targets in the treatment of human heart disease.
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PMID:The pathological role of transient receptor potential channels in heart disease. 1920 4