Cardiac activity

Only three of the metabolically active cardiac glycosides, namely digoxin, digitoxin, and lanatoside C, are commonly used in therapy. Digoxin is the form most frequently prescribed in the United Kingdom and the United States. 

Beta 2 Postsynaptic effector cells, especially smooth muscle and cardiac muscle Stimulation of adenylyl cyclase and increased cAMP. Activates cardiac G under some conditions. 

ACTIVE cardiac stimulant ACTIVE cardiac stimulant... 

The actual picture of the troponin head, however, could not have been fully anticipated before the recent crystal structures of the Ca2+-activated cardiac (not shown) and skeletal troponin head region (Fig. 6C and D), both of which contain all three subunits (Takeda et al., 2003) (Vinogradova et al., 2005). To be sure, one can easily recognize the previously observed or predicted features such as the IT coiled-coil in these structures, as well as the contacts made between the TnC lobes and... 

Atkinson, L. L., Fischer, M. A., and Lopaschuk, G. D. 2002. Leptin activates cardiac fatty acid oxidation independent of changes in the AMP-activated protein kinase-acetyl-CoA carboxylase-malonyl-CoA axis. J. Biol. Chem. 277 29424-29430. 

Lasley RD, Narayan P, Uittenbogaard A, Smart EJ. Activated cardiac adenosine Al receptors translocate out of caveolae. J Biol Chem 2000 275 4417-1421. 

Salata JJ, Jurkiewicz NK, Wang J, Evans BE, Orme HT, Sanguinetti MC. 1998. A novel benzodiazepine that activates cardiac slow delayed rectifier K+ currents. Mol. Pharmacol. 54 220-30... 

Although leptin is being derived primarily from adipocytes, it is now shown that non adipocyte tissues can be a source of leptin. In fact, gene expression of leptin and its receptors OB-Ra, OB -Rb and OB-Re have been identified in rat heart.46 It is likely that leptin serves an autocrine/paracrine role in regulating cardiac function. Leptin is shown to have a negative inotropic effect and promotes hypertrophy.47, 48 The physiological role of leptin in myocardial ischemia remains unknown. Leptin activates cardiac fatty acid oxidation independent of changes in the AMP-activated protein kinase-acetyl-CoA carboxylase-malonyl-CoA axis.49... 

Voacanga ajricana Liliaceae Antioxidant activity, cardiac spasms, caries, disinfectant, fatigue, amebic dysentery, asthma, diarrhea, edema, leprosy, convulsions in children, to calm the insane, epilepsy. 17, 31... 

Agonist 1 increases HR, presumably through direct activation of cardiac P receptors because the effect is blocked by propranolol but is not influenced by the alpha blocker (prazosin), the ganglion blocker (trimethaphan), or blockade of M receptors (atropine). Only two of the listed drugs directly activate cardiac receptors epinephrine and norepinephrine. For NE, any direct cardiac stimulation is counteracted by reflex bradycardia resulting from the increase in mean BP via its activation of a, receptors in blood vessels (it has no effects... 

To assess the mechanism by which protein Fv activates cardiac mast cells, the protein was preincubated with human monoclonal IgM of different VH families [63], Preincubation of mast cells with preparations of monoclonal IgM that possess a VH3 domain concentration-dependently inhibited the releasing activity of protein Fv. By contrast, preincubation with a monoclonal IgM Vh6+ had no such effect. These results suggest that binding to the VH3 domain inhibits the binding of protein Fv to IgE bound to FceRI on cardiac mast cells. 

Acrivastine enhances the CNS depressant effects of alcohol and other CNS depressants. Overdosage with pseudoephedrine may cause palpitations, tachycardia, pressor activity, cardiac arrhythmias, or cardiovascular collapse. These agents should not be taken with monoamine oxidase A inhibitor (MAO A inhibitor), such as tranylcypromine. 

Quinidine, Polymorphic VT with T QT EAD-related triggered activity Cardiac pacing Hypokalemia, bradycardia... 

Many tetrazoles are biologically active. 1,5-Pentamethylenetetrazole 10 (pentetrazol, Cardiazol) is the most widely known of such compounds. It is a CNS-active cardiac and respiratory stimulant and narcotic antagonist and is injected in cases of barbiturate poisoning. It is prepared via hexano-6-lactam by addition of sodium azide and sulfuric acid to cyclohexanone (Schmidt reaction) ... 

Xue T, Cho H C, Akar E G, et al. (2005). Eunctional integration of electrically active cardiac derivatives from genetically engineered human embryonic stem cells with quiescent recipient ventricular cardiomyocytes insights into the development of cell-based pacemakers. Circul. 111 11-20. 

Mathematical formulation. IEEE Trans. Biomed. Eng., yi 850-860, 1990. This paper and the companion paper below, describe the bidomain approach to the propagation of electrical signals through active cardiac tissue. 

The heart is an electromechanical system, in which mechanical pumping function is initiated and coordinated by automatic rhythmic cardiac electrical activity. Transient electrical disturbances m this activity (cardiac arrhythmias) can immediately cause death. The implantable cardioverter defibrillator (ICD) is a medical device that can be implanted in a human body and will automatically detect and treat cardiac arrhythmias. Mirowski et al. [1] first reported on a demonstration of a functioning ICD in 1970. In his demonstration, he induced a fatal ventricular tachyarrhythmia in a dog. The dog was then successfully and dramatically rescued by the automatic operation of a previously implanted ICD. The first report of successful ICD implantation in humans soon followed [2]. In subsequent decades, advances in ICD technology have reduced ICD size from more than 200 cm, originally, to as httle as 25 cm, while markedly improving functionality, reliability, and longevity. ICDs are now considered as standard of care for patients at risk for ventricular arrhythmia and are implanted in more than 150,000 patients per year in the United States alone [3]. 

Clinical interest in Mg + has increased recently, with the commercialization of Mg " " ISEs based on neutral carrier ionophores for benchtop clinical electrolyte instruments such as AVL and Nova [84]. Magnesium is important for neuronal activity, cardiac excitability, muscular contraction, and blood pressure, among other physiological roles it exists bound to proteins or to small anions and as free Mg +, but has traditionally been measured as total Mg. The recent availability of ISEs combined with the known decrease in dietary magnesium intake in the western world has stimulated clinical research that may have important implications in cardiac care [85] and diabetes [86], as it is now known that ionized Mg (free Mg +) levels can vary, whereas total Mg remains constant. 

The Multicenter InSync ICD Randomized Clinical Evaluation II (MIRACLE ICD II) was a follow-up randomized, double-blind, parallel-conlrolled clinical trial of CRT in New York Heart Association Functional Class II heart failure patients on optimal medical therapy with a left ventricular ejection fraction < 0.35, a QRS > 130ms and a Class I indication for an ICD. Patients were randomized to control group (ICD activated, CRT off) and to CRT group (ICD activated, cardiac-resynchronization therapy on). No significant differences were noted in 6-min walk distance or quality of life scores or peak V02. There were significant improvements in left ventricular diastolic and systolic volumes and in left ventricular ejection fraction (198). 

The heart is a supreme example of biomechanical engineering, and, under normal circumstances, it operates with elegant economy (Turner 1994). As acute metabolic demand varies with increases and decreases in skeletal muscular activity, cardiac activity adapts commensurately, enabling skeletal musculature to receive appropriate supplies of blood, and hence oxygen, to facihtate its physical activity. This intimate and biologically sensible arrangement is complemented by blood flow within the systemic vasculature, which (under normal circumstances) ensures adequate oxygen supply to all bodily tissues. 

Furukawa T, Bai CX, Kaihara A, Ozaki E, Kawano T, Nakaya Y, Awais M, Sato M, Umezawa Y, Kurokawa J (2006) Ginsenoside Re, a main phytosterol of Panax ginseng, activates cardiac potassium channels via a nongenomic pathway of sex hormones. Mol Pharmacol 70 1916-1924... 

Keywords Anticancer activity cardiac glycosides clinical implication mechanism... 

---