Related Experiment Videos
Aminophylline does not inhibit canine hypoxic pulmonary vasoconstriction
The American Review of Respiratory Disease
|December 1, 1982
Summary
Aminophylline did not inhibit hypoxic pulmonary vasoconstriction (HPV) in dogs. This suggests its effects on oxygenation in humans may stem from respiratory mechanics, not vasodilation or bronchodilation.
Area of Science:
- Pharmacology
- Pulmonary Physiology
- Respiratory Medicine
Background:
- Hypoxic pulmonary vasoconstriction (HPV) is a critical mechanism for matching ventilation and perfusion.
- Aminophylline, a bronchodilator, has potential vasodilatory and bronchodilatory effects that could influence HPV.
Purpose of the Study:
- To investigate the effect of intravenously administered aminophylline on acute in vivo lobar HPV in a canine model.
- To determine if aminophylline inhibits or alters the HPV response.
Main Methods:
- Eight pentobarbital-anesthetized dogs were used to model HPV by inducing selective left lower lobe (LLL) hypoxia.
- Aminophylline was administered intravenously before or after hypoxia induction, with serum theophylline levels monitored.
- LLL HPV responses were measured electromagnetically before and after aminophylline administration.
Main Results:
- Aminophylline administration resulted in serum theophylline levels of 12.0–15.1 µg/ml.
- The magnitude of LLL HPV responses after aminophylline (6 and 3 mg/kg) was not significantly different from control responses.
- No significant difference was observed between HPV responses when aminophylline was given before or after hypoxia.
Conclusions:
- Aminophylline does not inhibit acute in vivo lobar HPV in dogs.
- The impact of aminophylline on human arterial oxygenation may be primarily related to respiratory mechanics rather than a combination of vasodilator and bronchodilator effects.