Search results for "Myocardium"

Effects of nitroglycerin or pentaerithrityl tetranitrate treatment on the gene expression in rat hearts: evidence for cardiotoxic and cardioprotectiv…

2009

Nitroglycerin (NTG) and pentaerithrityl tetranitrate (PETN) are organic nitrates used in the treatment of angina pectoris, myocardial infarction, and congestive heart failure. Recent data show marked differences in the effects of NTG and PETN on the generation of reactive oxygen species. These differences are attributed to different effects of NTG and PETN on the expression of antioxidative proteins like the heme oxygenase-I. To analyze the expressional effects of NTG and PETN in a more comprehensive manner we performed whole genome expression profiling experiments using cardiac total RNA from NTG- or PETN-treated rats and DNA microarrays containing oligonucleotides representing 27,044 rat…

Some glutathione-related enzymic activities in skeletal muscle and myocardium of the rat : adaptations to endurance training

1991

Effect of chronic exercise on glucose uptake and activities of glycolytic enzymes measured regionally in rat heart.

1989

Regional glucose uptake in perfused hearts, and the activities of several glycolytic enzymes contributing to the glucose metabolism in perfused and nonperfused hearts were studied in male and female rats after 8–9 weeks of swimming training. The left ventricular glucose uptake showed a transmural gradient in the sedentary animals, the subendocardial uptake being 30% and 12% higher than that of the subepicardial layer in the males and females, respectively. Swimming exercise abolished the left ventricular glucose uptake gradient in male rats, and in female rats an opposite gradient was found, the subepicardial uptake being 23% higher than the subendocardial uptake. The activities of phosphof…

Depolarization-induced influx of sodium in response to phenylephrine in rat atrial heart muscle.

1991

1. The effects of alpha 1-adrenoceptor stimulation on transmembrane potential, currents and ion fluxes were investigated in multicellular preparations and/or single cells obtained from the left atrium of rat hearts. 2. In multicellular preparations, phenylephrine caused a concentration-dependent positive inotropic effect, an increase in action potential duration, and a decrease in resting potential; the effects were antagonized by phentolamine. 3. In the presence of phenylephrine (100 mumol/1), two levels of resting potential were observed when the preparations were, alternately, electrically stimulated or kept at rest (-74 +/- 1 mV during activity and -62 +/- 4 mV at rest; mean +/- S.E.M.;…

Right ventricular involvement in anterior myocardial infarction: a translational approach.

2010

Aims The aim of the present study was to evaluate the involvement of the right ventricle (RV) in reperfused anterior ST-elevation myocardial infarction (STEMI). Methods and results Left anterior descending (LAD)-perfused area (using thioflavin-S staining after selective infusion in proximal LAD artery, %), infarct size (using triphenyltetrazolium chloride staining, %), and salvaged myocardium (% of LAD-perfused area) in the right and left ventricle (LV) were quantified in a 90-min LAD occlusion 3-day reperfusion model in swine ( n = 8). Additionally, we studied, using cardiovascular magnetic resonance, 20 patients with a first STEMI due to proximal LAD occlusion treated with primary angiopl…

The effect of physostigmine on the vagally induced muscarinic inhibition of noradrenaline release from the isolated perfused rabbit atria.

1982

1. Presynaptic cholinergic-adrenergic interactions were studied on isolated perfused rabbit atria with the extrinsic right vagus and sympathetic innervation intact. The transmitter stores were labelled with 14C-choline and 3H-noradrenaline. The radioactive compounds were separated on columns and determined by scintillation spectrometry. The stimulation-evoked overflow of both transmitters was calcium-dependent and abolished by tetrodotoxin. 2. Methacholine caused a concentration-dependent decrease of atrial tension development and 3H-noradrenaline overflow evoked by 3 Hz sympathetic stimulation. Vagus nerve stimulation (1–20Hz), although nearly abolishing tension development at 20Hz, decrea…

The role of choline in the release of acetylcholine in isolated hearts.

1978

1. The concentrations of acetylcholine, choline and noradrenaline were estimated in the perfusate (overflow) of isolated hearts of chickens, cats, rabbits and guinea pigs. Neurotransmitter release was evoked by stimulation of both vagus nerves and by direct stimulation of the heart (field stimulation). 2. In the absence of exogenous choline and physostigmine, field stimulation at 20 Hz for 20 min caused an overflow of acetylcholine from the hearts of the 4 species investigated. During vagal stimulation, however, acetylcholine was detected only in the perfusate of the chicken heart. 3. Field stimulation for 2 min caused an overflow of 193 pmol g−1 min−1 acetylcholine and of 666 pmol g−1 min−…

The use of the de deckere-ten hoor preparation for study of nicotinic and potassium-evoked dopamine ?-hydroxylase release from the rabbit heart

1980

1. Dopamine β-hydroxylase (DBH) and noradrenaline were determined both in the venous effluent (perfusate) and in the transmyocardial fluid (TMF) collected from the apex of the rabbit isolated heart which was prepared according to De Deckere and Ten Hoor (1977) and perfused with Tyrode's solution at 20 ml/min. 2. Perfusion for 2 min with the nicotinic drug, p-aminophenethyl-trimethylammonium (PAPETA), both in the absence of presence of atropine evoked noradrenaline overflow into the perfusate and TMF that was maximal in the 0–2 min sample and declined from maximum with a t1/2 of 0.6 min. DBH was released into TMF with the maximum from 2–4 min and a t1/2 of decline of 5.6 min. 3. High K-low N…

INTERACTIONS OF ISOPRENALINE AND PROSTAGLANDIN E2 WITH RESPECT TO MYOCARDIAL CONTRACTILE FORCE, CORONARY VASCULAR RESISTANCE AND MYOCARDIAL OXYGEN CO…

1976

Left ventricular pressure (LVP), left ventricular pressure derivative (LV dp/dtmax), coronary vascular resistance (CVR) and myocardial oxygen consumption (Qo2) were measured simultaneously in isolated, electrically driven hearts of guinea-pigs at constant perfusion rate. 2 LVP, LV dp/dtmax, CVR and Qo2 were greatly decreased by either the addition of prostaglandin E2 (50 ng/ml) to the perfusion fluid or pretreatment of the animals with reserpine. 3 Isoprenaline (0.5 nM to 100 nM) induced increases in LVP, LV dp/dtmax and Qo2. In the presence of prostaglandin E2, there was a parallel shift of the isoprenaline concentration-response curve for LVP and LV dp/dtmax. This effect was not seen, aft…

La concentración sanguínea de PGC-1a predice miocardio salvado y remodelado ventricular tras infarto agudo de miocardio con elevación del segmento ST

2015

et al.