Related Experiment Videos
Elevated blood pressure in the embryonic chick induced by a teratogenic dose of dextroamphetamine sulfate
Insights
Dextroamphetamine sulfate causes cardiovascular defects in chick embryos by increasing blood pressure and decreasing heart rate. This study suggests elevated embryonic blood pressure is a key factor in malformation development.
Area of Science:
- Developmental biology
- Cardiovascular toxicology
- Teratology
Background:
- Dextroamphetamine sulfate is known to be cardiotoxic in developing embryos.
- Previous studies established its teratogenic effects on the cardiovascular system of chick embryos.
Purpose of the Study:
- To investigate the immediate cardiovascular effects of a teratogenic dose of dextroamphetamine sulfate in chick embryos.
- To determine the impact of d-amphetamine on embryonic blood pressure and heart rate during critical developmental stages.
Main Methods:
- Administration of dextroamphetamine sulfate (0.25 mg/egg) to 4-day-old chick embryos (stage 24).
- Measurement of mean ventricular blood pressure (MVBP) and heart rate at various time points post-treatment.
- Comparison of treated embryos with untreated and saline-treated controls using a water manometer system.
Main Results:
- A significant elevation in mean ventricular blood pressure (MVBP) was observed 4 hours after d-amphetamine administration, exceeding controls by 30%.
- A significant decrease in heart rate (6-9%) was noted at 2, 3, and 5 hours post-treatment compared to controls.
- The observed cardiovascular changes occurred during critical periods of aortic arch and ventricular septal morphogenesis.
Conclusions:
- Elevated embryonic blood pressure following d-amphetamine exposure is a potential etiological factor for cardiovascular malformations.
- The study highlights the acute cardiovascular effects of d-amphetamine during key embryonic development phases.
- These findings contribute to understanding the mechanisms of drug-induced teratogenicity.
Abstract:
Previous work has demonstrated the cardiovascular teratogenicity of dextroamphetamine sulfate (0.25 mg/egg) in the 4-day (stage 24) chick embryo. Our current studies indicate that embryos treated with this teratogenic dose of d-amphetamine exhibit a mean ventricular blood pressure (MVBP) elevation for 1 hour at 4 hours after treatment. The mean MVBP value 4 hours after d-amphetamine treatment significantly exceeded the mean MVBP value for combined untreated and saline controls by 30%. Furthermore, d-amphetamine significantly decreased heart rate relative to controls by 6-9% at 2, 3, and 5 hours after administration. Elevation of embryonic blood pressure (measured by a water manometer system) during a critical period of aortic arch and ventricular septal morphogenesis is suggested as an etiological factor in the genesis of malformations of these structures.