Action of adrenalin and noradrenalin on electrophysiological properties of smooth muscles of the portal vein

1970 ◽  
Vol 69 (2) ◽  
pp. 104-107
Author(s):  
V. M. Taranenko
Keyword(s):  
Portal Vein ◽  
Smooth Muscles ◽  
Electrophysiological Properties

scholarly journals Unrestricted Hepatocyte Transduction with Adeno-Associated Virus Serotype 8 Vectors in Mice

2005 ◽  
Vol 79 (1) ◽  
pp. 214-224 ◽  
Author(s):  
Hiroyuki Nakai ◽  
Sally Fuess ◽  
Theresa A. Storm ◽  
Shin-ichi Muramatsu ◽  
Yuko Nara ◽  
...  
Keyword(s):  
Portal Vein ◽  
Dose Response ◽  
Smooth Muscles ◽  
The Body ◽  
Specific Gene ◽  
High Dose ◽  
Adeno Associated Virus ◽  
Virus Serotype ◽  
High Doses ◽  
Dose Response Study

ABSTRACT Recombinant adeno-associated virus (rAAV) vectors can mediate long-term stable transduction in various target tissues. However, with rAAV serotype 2 (rAAV2) vectors, liver transduction is confined to only a small portion of hepatocytes even after administration of extremely high vector doses. In order to investigate whether rAAV vectors of other serotypes exhibit similar restricted liver transduction, we performed a dose-response study by injecting mice with β-galactosidase-expressing rAAV1 and rAAV8 vectors via the portal vein. The rAAV1 vector showed a blunted dose-response similar to that of rAAV2 at high doses, while the rAAV8 vector dose-response remained unchanged at any dose and ultimately could transduce all the hepatocytes at a dose of 7.2 × 1012 vector genomes/mouse without toxicity. This indicates that all hepatocytes have the ability to process incoming single-stranded vector genomes into duplex DNA. A single tail vein injection of the rAAV8 vector was as efficient as portal vein injection at any dose. In addition, intravascular administration of the rAAV8 vector at a high dose transduced all the skeletal muscles throughout the body, including the diaphragm, the entire cardiac muscle, and substantial numbers of cells in the pancreas, smooth muscles, and brain. Thus, rAAV8 is a robust vector for gene transfer to the liver and provides a promising research tool for delivering genes to various target organs. In addition, the rAAV8 vector may offer a potential therapeutic agent for various diseases affecting nonhepatic tissues, but great caution is required for vector spillover and tight control of tissue-specific gene expression.

Dependence of Ca2+ channel currents on endogenous and exogenous sources of ATP in portal vein smooth muscle

1997 ◽  
Vol 272 (2) ◽  
pp. H987-H994 ◽  
Author(s):  
J. N. Lorenz ◽  
R. J. Paul
Keyword(s):  
Portal Vein ◽  
Smooth Muscles ◽  
Channel Activity ◽  
Vascular Smooth Muscles ◽  
Vascular Contractility ◽  
Channel Current ◽  
Metabolic Substrates ◽  
Oxidative Processes ◽  
Myosin Interaction ◽  
Channel Currents

Metabolic pathways in vascular smooth muscles (VSM) appear to be functionally compartmentalized such that glycolysis fuels membrane-related processes, whereas oxidative processes fuel actin-myosin interaction. Because ATP influences Ca2+ channel activity, we examined the effects of ATP and metabolic substrates on Ca2+ channel activity with patch-clamp techniques in VSM cells isolated from rat portal vein. The peak magnitude of the Ca2+ channel currents was found to depend on the ATP concentration in the patch pipette. Cells perfused with 1, 3, and 5 mMATP had mean peak currents of 4.7 +/- 0.6, 12.2 +/- 1.9, and 17.6 +/- 2.0 pA/pF, respectively, and all currents showed substantial rundown. In separate experiments performed in the absence of intracellular ATP, provision of glycolytic but not oxidative substrates was able to maintain Ca2+ channel currents at levels comparable with those seen in the presence of 1 mM ATP. In the presence of 5 mM ATP, provision of glycolytic substrates resulted in a high peak current amplitude that was also very stable. Finally, metabolic inhibition with cyanide and iodoacetate caused a significant increase in the rate of current rundown, even in the presence of 5 mM ATP. These findings indicate that Ca2+ channel current is strongly dependent on ATP and that the source of ATP can also be an important factor. Compared with exogenous provision of ATP, endogenous metabolism preferentially maintained Ca2+ channel currents, consistent with the hypothesis of a functionally separate subsarcolemmal compartment. This provides an effective pathway for linking E-C coupling and vascular contractility to the metabolic state of the vascular cell.

scholarly journals Effects of oxyfedrine on isolated portal vein and other smooth muscles

1973 ◽  
Vol 47 (4) ◽  
pp. 827-837 ◽  
Author(s):  
J. E. MACKENZIE ◽  
J. R. PARRATT
Keyword(s):  
Portal Vein ◽  
Smooth Muscles

scholarly journals Involvement of the vanilloid receptor 1 in the mechanism of analgetic effect of ketorolac

2013 ◽  
Vol 60 (2) ◽  
pp. 49-55
Author(s):  
Yadlovskyi O. ◽  
Bukhtiarova T. ◽  
Bobkova L. ◽  
Tatianchenko I. ◽  
Monchak I.
Keyword(s):  
Portal Vein ◽  
Initial Level ◽  
Smooth Muscles ◽  
Tail Flick ◽  
Active Centre ◽  
Vanilloid Receptor 1 ◽  
Antinociceptive Effects ◽  
Agonist And Antagonist

Abstract The existing ideas about the ketorolac mechanism of analgetic potency are associated with its effect on COX isoenzymes and its significant potency needs to be explained more completely. Its impact on vanilloid receptors 1 (TRPV1) can also be an effective mechanism of analgetic action. We have evaluated the analgetic potential of ketorolac on the basis of its influence on TRPV1. It is known that Tyr511 and Ser512 amino acids are active central components of TRPV1. Thereby the synthesis of the dipeptide Tyr-Ser has been conducted as a model of the TRPV1 active centre. In our model test, using spectrofluorometry, the formation of intermolecular complexes was shown: “ketorolac - Tyr-Ser” and “capsaicin - Tyr-Ser” at stability constants Kr=0.53 • 10-4 L/mol; Kkor= 0.998 and Kr =0.3 • 10-4 L/mol; Kkor=0.998, respectively. Verification of the data was proved in experiments in vitro (the preparation of portal vein) and in vivo (Tail-flick model), with the TRPV1 agonist and antagonist. On portal vein, it was established (from initial level) by Krebs solution that the range of relaxation of smooth muscles of the portal vein (SM) was as follows at the concentration of capsaicin 0.1 μmol/L +30.3%±5.3%, capsazepine 0.5 μmol/L -3.2±2.7% and ketorolac 1.0 μmol/L -60.0±7.0%. In the experiment, at the above mentioned doses of ketorolac on the background of the action of the capsaicin (capsazepine), the range of relaxation of smooth muscles (SM) of the portal vein was -59.3±5.0% and -63.0±6.0% respectively testifying to the fact that the effect of capsaicinoids was neutralised by ketorolac. On the Tail-flick model, an atypical potentiation of the ketorolac antinociception at simultaneous use with the capsaicin was shown. The obtained data allow suggesting that TRPV1 can activate the ketorolac antinociceptive effects.

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