Drugs online research references
Agents Actions Suppl. 1992;38 ( Pt 3):209-16.
Ramiprilat prevents PAF-induced myocellular and endothelial injury in a neutrophil-perfused heart preparation.
Schror K, Felsch A.
Institut fur Pharmakologie, Heinrich-Heine-Universitat Dusseldorf, F.R.G.
This study investigates the action of PAF-stimulated human polymorphonuclear leukocytes (PMN) on myocardial integrity and function in Langendorff-perfused guinea-pig hearts. Infusion of 10(6) PMN/ml resulted in a negative inotropic effect without larger biochemical evidence for myocardial tissue injury while infusion of PAF (1 microM) did not cause any permanent effect at all. However, the combined administration of PAF-stimulated PMN resulted in severely depressed myocardial contractile function and biochemical evidence for myocardial tissue injury. This was probably due to an enhanced uptake of PMN from the coronary perfusate and accumulation within the myocardial tissue. Ramiprilat, (10 microM) significantly improved left ventricular function and myocardial cell integrity. Similar results were obtained with bradykinin (1 nM). The data suggest a PAF-induced, PMN-mediated myocardial tissue injury as well as cardioprotective actions of ACE inhibition which are possibly related to stimulation of the kinin/prostacyclin axis.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1334351&dopt=Abstract
J Mol Cell Cardiol. 1997 Nov;29(11):2941-51.
Contractile function of papillary muscle from rats with different infarct size after beta-adrenergic blockade and ACE-inhibition.
Wagner KD, Theres H, Born A, Strube S, Wunderlich N, Pfitzer G, Baumann G, Gunther J.
Clinic Internal Medicine I, Humboldt-University, Berlin, 10098, Germany.
We tested whether ACE-inhibition with ramipril (A), beta-adrenergic blockade with metoprolol (beta) or combined treatment (beta A) for 6 weeks after inducing myocardial infarction in rats by left coronary artery ligation modifies contractile function of hypertrophied papillary muscle from left ventricles with different infarct size (IS) compared to a placebo group (P). At IS<40% of left ventricle, contraction and relaxation were less impaired than at IS>40% compared to sham operated rats (SO). Isometrically developed peak force and calcium sensitivity of myofilaments, measured in skinned fibres, were significantly higher in beta. Treatment with ramipril or metoprolol improved contraction rate and force development, respectively, mainly at IS<40%, but deteriorated relaxation rate. ACE-inhibition and beta-adrenergic blockade had no significant improving effect on the relaxation rate and further characteristics of the contractile function at IS>40%, although combined treatment reduced the infarct size and ramipril treatment suppressed the development of hypertrophy. Post-extrastimulatory potentiation was increased in beta and beta A at IS>40%. Post-rest potentiations were influenced hardly at IS<40% and were significantly smaller in A at IS>40%. The twitch-to-twitch decay of the potentiations was faster at IS>40%. Increase in the degree of post-extrastimulatory potentiation, steeper twitch-dependent decay of the potentiations and loss of rest-dependent potentiation at IS>40% indicate relatively increased trans-sarcolemmal Ca2+ transports via Ca2+ channels and Na+/Ca2+ exchange, partly modified by ramipril and metoprolol. The results demonstrate that ACE-inhibition and beta-adrenergic blockade induce a dissociation between trophic effects and phenotypic effects on contractile function after chronic infarction. Copyright 1997 Academic Press Limited.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=9405169&dopt=Abstract
Pflugers Arch. 1989 Dec;415(3):342-50.
Contraluminal para-aminohippurate (PAH) transport in the proximal tubule of the rat kidney. VI. Specificity: amino acids, their N-methyl-, N-acetyl- and N-benzoylderivatives; glutathione- and cysteine conjugates, di- and oligopeptides.
Ullrich KJ, Rumrich G, Wieland T, Dekant W.
Max-Planck-Institut fur Biophysik, Frankfurt/Main, Federal Republic of Germany.
In order to evaluate the specificity of the renal contraluminal PAH transport system for amino acids, oligopeptides and their conjugates, the inhibitory potency of these substances against contraluminal [3H] PAH influx has been determined. For this, inhibition of 3H-PAH flux from the interstitium into cortical tubular cells of the rat kidney in situ has been measured. Apparent Ki values were evaluated by a computer program assuming competitive inhibition. Unconjugated amino acids (glycine, cysteine, alanine, leucine, phenylalanine, tyrosine, aspartate, glutamate, arginine, ornithine and lysine) do not inhibit [3H] PAH influx. The very hydrophobic tryptophan, however, does. N-alpha-methylation does not change this behaviour. N-alpha-acetylation does not evoke interaction with the PAH transporter when it occurs with glycine, cysteine (to yield mercapturic acid), arginine, ornithine and lysine. However, it renders alanine, leucine, phenylalanine, tryptophan, L-aspartate moderately, and L-glutamate strongly, inhibitory. The acetylated D-isomers of alanine, leucine and phenylalanine exert a higher inhibitory potency compared with the respective L-isomers. N-alpha-benzoylation of L-lysine is ineffective. N-alpha-benzoylation, however, evokes interaction with the PAH transporter, when it occurs with ornithine less than arginine less than histidine less than glycine = leucine less than alanine = phenylalanine = aspartate = glutamate. Dipeptides interact with the PAH transporter according to their hydrophobicity (Nozaki scale down to 0.9, Fauchere scale up to 1.0). N-acetylation does not change this behaviour. Hydrophobicity also renders oligopeptides, as angiotensin II, inhibitory against PAH transport. Similarly the anionic angiotensin I converting enzyme inhibitors Captopril, Enalapril and Ramipril inhibit contraluminal PAH influx.
online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2622761&dopt=Abstract
Herbs and Pharmaceuticals Online ||
Hair Million herbal formula for hair loss and hair growth ||
Wellstreet online pharmacy for click-order prescription medications ||
Altace Online Pharmacy ||
Rx Drugs USA, Prescription Drugs Online Pharmacy ||
Insurance plans and information ||
Insurance policies for all purposes ||
Antibiotics and prescription medications online literature ||