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A Rapid and Specific Microplate Assay for the Determination of Intra- and Extracellular Ascorbate in Cultured Cells
Published on: April 11, 2014
Potentiation of isoproterenol effect by ascorbic acid
Research Communications in Chemical Pathology and Pharmacology
|August 1, 1976
Summary
Administering isoproterenol with ascorbic acid into the small intestine potentiated its cardiovascular effects in dogs. This interaction was not observed when the substances were given intravenously, suggesting a route-specific effect.
Area of Science:
- Pharmacology
- Cardiovascular Physiology
- Gastrointestinal Drug Absorption
Background:
- Isoproterenol is a non-selective beta-adrenergic agonist used to treat bradycardia and hypotension.
- Ascorbic acid (vitamin C) is an essential nutrient with antioxidant properties.
- The gastrointestinal tract plays a crucial role in drug absorption and metabolism.
Purpose of the Study:
- To investigate the potential synergistic effect of ascorbic acid on the cardiovascular actions of isoproterenol when administered intraduodenally.
- To compare the effects of intraduodenal versus intravenous co-administration of isoproterenol and ascorbic acid.
Main Methods:
- Anesthetized dogs were used as the experimental model.
- Isoproterenol was administered alone and in combination with ascorbic acid via both intraduodenal and intravenous routes.
- Cardiovascular parameters including heart rate, pulse pressure, and mean blood pressure were monitored.
Main Results:
- Intraduodenal co-administration of isoproterenol and ascorbic acid resulted in a significantly greater increase in heart rate and pulse pressure, and a more pronounced decrease in mean blood pressure compared to isoproterenol alone.
- Intravenous co-administration of isoproterenol and ascorbic acid did not produce a potentiating effect on the cardiovascular parameters.
Conclusions:
- Ascorbic acid potentiates the cardiovascular effects of isoproterenol when administered intraduodenally in dogs.
- The route of administration is critical for the observed interaction between isoproterenol and ascorbic acid.
- These findings suggest a potential role for gastrointestinal absorption or local effects in modulating drug interactions.
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