What question did this study set out to answer?

To determine whether platelet-activating factor alters in vivo coronary blood flow patterns and induces cyclic flow variations in a canine model of concentric coronary artery stenosis.

August 1, 1985CirculationOpen Access

Cyclic blood flow variations induced by platelet-activating factor in stenosed canine coronary arteries despite inhibition of thromboxane synthetase, serotonin receptors, and alpha-adrenergic receptors.

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Why the study?

Does platelet-activating factor induce cyclic flow variations in stenosed canine coronary arteries despite inhibition of thromboxane synthetase, serotonin receptors, and alpha-adrenergic receptors?

Population

39 male mongrel dogs with concentric coronary artery stenosis

Comparison

Platelet-activating factor infusion (10 or 10… vs Baseline state and state after administration of…

Design

Preclinical

Authors

PAPhillip ApprillUniversity of Texas Health Science Center at Dallas JSJoy M. SchmitzThe University of Texas Health Science Center at Houston WCWilliam B. CampbellGeneral / Preventive / Lipids

Discussion

Member takes

Overview

PAF may mediate cyclic flow variations independently in stenosed arteries; extends mechanistic models in canines but leaves open human relevance.

Key Points

To determine whether platelet-activating factor alters in vivo coronary blood flow patterns and induces cyclic flow variations in a canine model of concentric coronary artery stenosis.
Studied 39 male mongrel dogs across three experimental protocols using a model of concentric coronary artery stenosis.
Infused intracoronary platelet-activating factor (10⁻⁹ or 10⁻⁸ mol/min) to evaluate cyclic flow variations and systemic hemodynamic responses.
Administered pharmacological inhibitors—UK38485 (mean 2.2 mg/kg), ketanserin (0.5 mg/kg), or yohimbine (2 mg/kg)—followed by platelet-activating factor re-infusion and measurement of distal coronary thromboxane B2.
Intracoronary platelet-activating factor induced cyclic flow variations in 3 of 6 dogs, decreasing mean arterial pressure by 5.5% at low dose and 42.1% at high dose at 10 minutes post-infusion.
Abolished cyclic flow variations were restored to pre-antagonist frequencies upon subsequent administration of platelet-activating factor despite prior blockade by UK38485, ketanserin, or yohimbine.
Thromboxane synthetase inhibition normalized elevated thromboxane B2 levels, but subsequent platelet-activating factor re-established cyclic flow variations without altering coronary arterial thromboxane B2 levels.

Structured PICO

Does platelet-activating factor induce cyclic flow variations in stenosed canine coronary arteries despite inhibition of thromboxane synthetase, serotonin receptors, and alpha-adrenergic receptors?

Population

39 male mongrel dogs with concentric coronary artery stenosis

Intervention

Platelet-activating factor (PAF) infusion (10(-9) or 10(-8) mol/min) into the coronary artery proximal to the stenosis, administered alone or after inhibitors

Comparator

Baseline state and state after administration of inhibitors (thromboxane synthetase inhibitor UK38485, serotonin antagonist ketanserin, or alpha 2-adrenergic antagonist yohimbine)

Outcome

Cyclic flow variations in coronary blood flowsurrogate

Platelet-activating factor can induce and restore cyclic coronary flow variations in stenosed arteries independent of thromboxane A2, serotonin, and alpha-adrenergic pathways.

Cite This Study

Apprill et al. (1985) studied this question.

synapsesocial.com/papers/6a87dab49f534feb2aad262c https://doi.org/10.1161/01.cir.72.2.397

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August 1, 1985CirculationOpen Access

Cyclic blood flow variations induced by platelet-activating factor in stenosed canine coronary arteries despite inhibition of thromboxane synthetase, serotonin receptors, and alpha-adrenergic receptors.

View Full Paper

Ask AI

Bookmark

Why the study?

Does platelet-activating factor induce cyclic flow variations in stenosed canine coronary arteries despite inhibition of thromboxane synthetase, serotonin receptors, and alpha-adrenergic receptors?

Population

39 male mongrel dogs with concentric coronary artery stenosis

Comparison

Platelet-activating factor infusion (10 or 10… vs Baseline state and state after administration of…

Design

Preclinical

Authors

PAPhillip ApprillUniversity of Texas Health Science Center at Dallas JSJoy M. SchmitzThe University of Texas Health Science Center at Houston WCWilliam B. CampbellGeneral / Preventive / Lipids

Discussion

Member takes

Overview

PAF may mediate cyclic flow variations independently in stenosed arteries; extends mechanistic models in canines but leaves open human relevance.

Key Points

To determine whether platelet-activating factor alters in vivo coronary blood flow patterns and induces cyclic flow variations in a canine model of concentric coronary artery stenosis.
Studied 39 male mongrel dogs across three experimental protocols using a model of concentric coronary artery stenosis.
Infused intracoronary platelet-activating factor (10⁻⁹ or 10⁻⁸ mol/min) to evaluate cyclic flow variations and systemic hemodynamic responses.
Administered pharmacological inhibitors—UK38485 (mean 2.2 mg/kg), ketanserin (0.5 mg/kg), or yohimbine (2 mg/kg)—followed by platelet-activating factor re-infusion and measurement of distal coronary thromboxane B2.
Intracoronary platelet-activating factor induced cyclic flow variations in 3 of 6 dogs, decreasing mean arterial pressure by 5.5% at low dose and 42.1% at high dose at 10 minutes post-infusion.
Abolished cyclic flow variations were restored to pre-antagonist frequencies upon subsequent administration of platelet-activating factor despite prior blockade by UK38485, ketanserin, or yohimbine.
Thromboxane synthetase inhibition normalized elevated thromboxane B2 levels, but subsequent platelet-activating factor re-established cyclic flow variations without altering coronary arterial thromboxane B2 levels.

Structured PICO

Does platelet-activating factor induce cyclic flow variations in stenosed canine coronary arteries despite inhibition of thromboxane synthetase, serotonin receptors, and alpha-adrenergic receptors?

Population

39 male mongrel dogs with concentric coronary artery stenosis

Intervention

Platelet-activating factor (PAF) infusion (10(-9) or 10(-8) mol/min) into the coronary artery proximal to the stenosis, administered alone or after inhibitors

Comparator

Baseline state and state after administration of inhibitors (thromboxane synthetase inhibitor UK38485, serotonin antagonist ketanserin, or alpha 2-adrenergic antagonist yohimbine)

Outcome

Cyclic flow variations in coronary blood flowsurrogate

Platelet-activating factor can induce and restore cyclic coronary flow variations in stenosed arteries independent of thromboxane A2, serotonin, and alpha-adrenergic pathways.

Cite This Study

Apprill et al. (1985) studied this question.

synapsesocial.com/papers/6a87dab49f534feb2aad262c https://doi.org/10.1161/01.cir.72.2.397

Also Consider

Synapse has enriched 4 closely related papers on similar clinical questions. Consider them for comparative context:

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