We measured [3H]PN200-110 binding and patch-clamp currents in rabbit ventricular myocytes to determine if there is a disparity between the density of dihydropyridine-specific receptors and functional L-type calcium channels, as has been reported for skeletal muscle. The dihydropyridine receptor density was 74.7 +/- 4.2 fmol/mg protein (mean +/- SEM, Kd = 1.73 +/- 0.29 nM, n = 6) in ventricular ...

Exogenous administration of arachidonic acid, prostaglandins PGF2 alpha, PGD2 and PGE2 increased potassium-stimulated uptake of calcium in rat brain synaptosomes from the brain of the rat, but had no effect on the basal uptake of calcium. Arachidonic acid-induced uptake of calcium was mediated by its prostaglandin metabolites, because a cyclooxygenase inhibitor, indomethacin, inhibited the resp...

A model of the ryanodine receptor (RyR) calcium channel is used to study the energetics of binding selectivity of Ca(2+) versus monovalent cations. RyR is a calcium-selective channel with a DDDD locus in the selectivity filter, similar to the EEEE locus of the L-type calcium channel. While the affinity of RyR for Ca(2+) is in the millimolar range (as opposed to the micromolar range of the L-typ...

Objective(s): Thyroid hormones play an essential role in fetal growth and maternal hypo-thyroidism which leads to cardiovascular deficiency in their offspring.  Considering this, we intended to investigate the impact of gestational hypothyroidism on offspring vascular contractibility and possible underlying mechanisms. Materials and Methods: Hypothyroidism was induced in female rats by administ...

23 24 The L-type Ca channel is the main route for calcium entry into cardiac myocytes 25 and it is essential for contraction. Alterations in whole cell L-type Ca channel 26 current and Ca homeostasis have been implicated in the development of 27 cardiomyopathies. Cytoskeletal proteins can influence whole cell L-type Ca current 28 and mitochondrial function. Duchenne Muscular Dystrophy is a fata...