Dantrolene is a drug that suppresses intracellular Ca(2+) release from sarcoplasmic reticulum (SR) in skeletal muscle and is used as a therapeutic agent in individuals susceptible to malignant hyperthermia. Although its precise mechanism of action has not been elucidated, we have identified the N-terminal region (amino acids 1-1400) of the skeletal muscle isoform of the ryanodine receptor (RyR1...

Li, Yanyan, Peili Wang, Jianchao Xu, and Gary V. Desir. Voltagegated potassium channel Kv1.3 regulates GLUT4 trafficking to the plasma membrane via a Ca -dependent mechanism. Am J Physiol Cell Physiol 290: C345–C351, 2006; doi:10.1152/ajpcell.00091.2005.— Kv1.3 is a voltage-gated K channel expressed in insulin-sensitive tissues. We previously showed that gene inactivation or pharmacological inh...

The rat diaphragm was used as an in vitro model for studies of contractures synergistically-induced by halothane and suxamethonium. The effects of three agents reported to inhibit phospholipase A2 activity (quinacrine, spermine and indomethacin), tubocurarine and dantrolene were examined on these contractures. Contractures induced by 1% halothane (0.26 +/- 0.02 g) (mean +/- SEM) were increased ...

Kynurenic acid (KYNA), the only known endogenous glutamate antagonist, is produced in the brain by kynurenine aminotransferases (KATs) I and II. Mitochondrial toxins, 1-methyl-4-phenylpyridinium (MPP +) and 3-nitropropionic acid (3-NPA), were previously shown to reduce KYNA synthesis via interference with KAT I and II. Data presented here demonstrate that immunophilin ligand, FK506 (10-130 micr...

Age-associated memory impairments may result as a consequence of neuroinflammatory induction of intracellular calcium (Ca(+2)) dysregulation. Altered L-type voltage-dependent calcium channel (L-VDCC) and ryanodine receptor (RyR) activity may underlie age-associated learning and memory impairments. Various neuroinflammatory markers are associated with increased activity of both L-VDCCs and RyRs,...

MDMA (3,4-methylenedioxymethamphetamine), popularly known as “Ecstasy,” was first introduced and patented by Merck & Co., Inc., in 1914 as an appetite suppressant. Currently, its primary role is as an illegal stimulant used to produce a euphoric effect during parties. This case report de scribes a 31-year-old man who, after taking 3 tablets of Ecstasy, presented to an emergency department with ...