Electrolyte Alterations in Vascular Smooth Muscle and Hypotensive Activity of a New Chalcone derivative

1968 ◽  
Vol 57 (5) ◽  
pp. 733-737 ◽  
Author(s):  
Gerald P. Sherman ◽  
Elias W. Packman ◽  
G.Victor Rossi
Keyword(s):  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Hypotensive Activity ◽  
Chalcone Derivative

Effects of the β-Receptor Antagonists Propranolol, Oxprenolol and Labetalol on Human Vascular Smooth-Muscle Contraction

1978 ◽  
Vol 55 (3) ◽  
pp. 235-240
Author(s):  
R. F. W. Moulds ◽  
R. A. Jauernig ◽  
J. D. Hobson ◽  
J. Shaw
Keyword(s):  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Barium Chloride ◽  
Smooth Muscle Contraction ◽  
Hypotensive Activity ◽  
Inhibitory Effects ◽  
Vascular Effects ◽  
High Concentrations ◽  
Β Receptor

1. Spiral strips of human digital arteries have been studied in vitro to investigate whether dl-propranolol, d-propranolol, oxprenolol and labetalol have peripheral vascular effects in man. 2. Labetalol was a potent inhibitor of contractile responses to noradrenaline, but had less effect on responses to 5-hydroxytryptamine and barium chloride. 3. dl-and d-propranolol were equally effective inhibitors of responses to barium chloride. They were only weak antagonists of noradrenaline responses, but stronger, non-competitive antagonists of 5-hydroxytryptamine responses. 4. Oxprenolol was only a weak inhibitor of the responses to both noradrenaline and 5-hydroxytryptamine and had little effect on responses to barium chloride. 5. It is concluded that labetalol has specific α-adrenoreceptor-blocking properties, which are probably relevant to its therapeutic action in man. Propranolol has non-specific inhibitory effects on vascular smooth muscle, which might contribute to its hypotensive activity at high concentrations, but oxprenolol has only slight peripheral effects that are probably therapeutically insignificant.

Neuronal and Extraneuronal Uptake of 3H-Norepinephrine in the Heart of the Active Bat: An Electron Microscopic Radioautographic Study

1973 ◽  
Vol 31 ◽  
pp. 522-523
Author(s):  
Martin Hagopian ◽  
Michael D. Gershon ◽  
Eladio A. Nunez
Keyword(s):  
Smooth Muscle ◽  
Monoamine Oxidase ◽  
Vascular Smooth Muscle ◽  
Cardiac Muscle ◽  
Maximum Rate ◽  
External Medium ◽  
Extraneuronal Uptake ◽  
Electron Microscopic ◽  
Cardiac Tissues ◽  
High Affinity

The ability of cardiac tissues to take up norepinephrine from an external medium is well known. Two mechanisms, called Uptake and Uptake respectively by Iversen have been differentiated. Uptake is a high affinity system associated with adrenergic neuronal elements. Uptake is a low affinity system, with a higher maximum rate than that of Uptake. Uptake has been associated with extraneuronal tissues such as cardiac muscle, fibroblasts or vascular smooth muscle. At low perfusion concentrations of norepinephrine most of the amine taken up by Uptake is metabolized. In order to study the localization of sites of norepinephrine storage following its uptake in the active bat heart, tritiated norepinephrine (2.5 mCi; 0.064 mg) was given intravenously to 2 bats. Monoamine oxidase had been inhibited with pheniprazine (10 mg/kg) one hour previously to decrease metabolism of norepinephrine.

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