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Updated: May 27, 2026

In vitro Measurements of Tracheal Constriction Using Mice
Published on: June 25, 2012
Influence of triiodothyronine on the contractile effect of D-nor-pseudoephedrine
Carlos Castillo-Henkel1, Jorge López-Canales, María del Carmen Castillo-Hernández
1Instituto Nacional de Perinatología, I.P.N., México. drcarloscastillo@hotmail.com
Abstract:
Here we contrast the vascular smooth muscle contractility produced by D-nor-pseudoephedrine, alone or combined with triiodothyronine, on the aorta and coronary vasculature of the rat. At high concentrations (greater than those found in normal therapeutic dosing) D-nor-pseudoephedrine contracted the aorta. In contrast, it produced vasodilation on pre-contracted aorta independently of the vasoconstrictor employed or the presence of vascular endothelium. D-nor-pseudoephedrine increased coronary perfusion pressure, but the effect was smaller than the vasoconstriction produced by phenylephrine (a full alpha 1 adrenergic agonist), and was blocked by the pre-treatment with triiodothyronine. These results suggest cardiovascular risks in the use of D-nor-pseudoephedrine for weight loss.
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