What question did this study set out to answer?

To clarify the relationship between post-ischemic myocardial dysfunction and local cardiac sympathetic nerve function during early reperfusion.

January 1, 1991Japanese Circulation Journal-english EditionOpen Access

Ventricular wall motion and NE release in post-ischemic reperfused myocardium.

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Why the study?

Does sympathetic nerve stimulation or norepinephrine administration affect ventricular wall motion and norepinephrine release in post-ischemic reperfused myocardium in dogs?

Population

32 mongrel dogs subjected to 15 minutes of coronary occlusion by balloon occluder followed by 60 minutes of…

Comparison

Sympathetic nerve stimulation alone… vs Baseline measurements before occlusion and…

Design

Preclinical

Follow-up

60 minutes of reperfusion

Authors

EKE KomatsuYamagata University HFH FukuyamaKyoto University TMT MisawaNagano Matsushiro General Hospital

Discussion

Member takes

Implication

Hypothesis-generating for alpha-2 mediated sympathetic impairment post-reperfusion in dogs; leaves open clinical translation or therapeutic targeting.

Key Points

To clarify the relationship between post-ischemic myocardial dysfunction and local cardiac sympathetic nerve function during early reperfusion.
Assigned 32 mongrel dogs to 3 experimental groups following 15 minutes of balloon coronary occlusion and 60 minutes of reperfusion: sympathetic nerve stimulation alone (Group 1, n=14), sympathetic stimulation with yohimbine pre-treatment (Group 2, n=9), or exogenous norepinephrine infusion (Group 3, n=9).
Measured regional myocardial length to determine systolic delta-shortening and quantified local norepinephrine release before occlusion and after reperfusion.
Evaluated the impact of sympathetic denervation in Group 1 using a 90% phenol solution.
In Group 1, systolic delta-shortening decreased significantly at 5 minutes post-reperfusion before progressively augmenting, accompanied by a sustained reduction in myocardial norepinephrine release that failed to recover over 60 minutes.
Group 2 (yohimbine pre-treated) and Group 3 (exogenous norepinephrine) exhibited no reduction in systolic delta-shortening during early reperfusion, with Group 2 maintaining baseline norepinephrine release.
Phenol denervation further decreased norepinephrine release in Group 1, demonstrating that nerve conduction remained intact but was suppressed by presynaptic alpha-2 receptor-mediated negative feedback.

Structured PICO

Does sympathetic nerve stimulation or norepinephrine administration affect ventricular wall motion and norepinephrine release in post-ischemic reperfused myocardium in dogs?

Population

32 mongrel dogs subjected to 15 minutes of coronary occlusion by balloon occluder followed by 60 minutes of reperfusion.

Intervention

Sympathetic nerve stimulation alone (n=14), pre-treatment with yohimbine hydrochloride (0.2 mg/kg) followed by sympathetic nerve stimulation (n=9), or exogenous norepinephrine administration (n=9).

Comparator

Baseline measurements before occlusion and comparisons between the three intervention groups.

Outcome

Regional myocardial length (systolic shortening) and norepinephrine (NE) release.surrogate

Diminished norepinephrine release, likely mediated by pre-synaptic alpha-2 receptor negative feedback, contributes to reduced sympathetic responsiveness in post-ischemic reperfused myocardium.

Cite This Study

Komatsu et al. (1991) studied this question.

synapsesocial.com/papers/6a97f5883de45e4adad7d226 https://doi.org/10.1253/jcj.55.900

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January 1, 1991Japanese Circulation Journal-english EditionOpen Access

Ventricular wall motion and NE release in post-ischemic reperfused myocardium.

View Full Paper

Ask AI

Bookmark

Why the study?

Does sympathetic nerve stimulation or norepinephrine administration affect ventricular wall motion and norepinephrine release in post-ischemic reperfused myocardium in dogs?

Population

32 mongrel dogs subjected to 15 minutes of coronary occlusion by balloon occluder followed by 60 minutes of…

Comparison

Sympathetic nerve stimulation alone… vs Baseline measurements before occlusion and…

Design

Preclinical

Follow-up

60 minutes of reperfusion

Authors

EKE KomatsuYamagata University HFH FukuyamaKyoto University TMT MisawaNagano Matsushiro General Hospital

Discussion

Member takes

Implication

Hypothesis-generating for alpha-2 mediated sympathetic impairment post-reperfusion in dogs; leaves open clinical translation or therapeutic targeting.

Key Points

To clarify the relationship between post-ischemic myocardial dysfunction and local cardiac sympathetic nerve function during early reperfusion.
Assigned 32 mongrel dogs to 3 experimental groups following 15 minutes of balloon coronary occlusion and 60 minutes of reperfusion: sympathetic nerve stimulation alone (Group 1, n=14), sympathetic stimulation with yohimbine pre-treatment (Group 2, n=9), or exogenous norepinephrine infusion (Group 3, n=9).
Measured regional myocardial length to determine systolic delta-shortening and quantified local norepinephrine release before occlusion and after reperfusion.
Evaluated the impact of sympathetic denervation in Group 1 using a 90% phenol solution.
In Group 1, systolic delta-shortening decreased significantly at 5 minutes post-reperfusion before progressively augmenting, accompanied by a sustained reduction in myocardial norepinephrine release that failed to recover over 60 minutes.
Group 2 (yohimbine pre-treated) and Group 3 (exogenous norepinephrine) exhibited no reduction in systolic delta-shortening during early reperfusion, with Group 2 maintaining baseline norepinephrine release.
Phenol denervation further decreased norepinephrine release in Group 1, demonstrating that nerve conduction remained intact but was suppressed by presynaptic alpha-2 receptor-mediated negative feedback.

Structured PICO

Does sympathetic nerve stimulation or norepinephrine administration affect ventricular wall motion and norepinephrine release in post-ischemic reperfused myocardium in dogs?

Population

32 mongrel dogs subjected to 15 minutes of coronary occlusion by balloon occluder followed by 60 minutes of reperfusion.

Intervention

Sympathetic nerve stimulation alone (n=14), pre-treatment with yohimbine hydrochloride (0.2 mg/kg) followed by sympathetic nerve stimulation (n=9), or exogenous norepinephrine administration (n=9).

Comparator

Baseline measurements before occlusion and comparisons between the three intervention groups.

Outcome

Regional myocardial length (systolic shortening) and norepinephrine (NE) release.surrogate

Diminished norepinephrine release, likely mediated by pre-synaptic alpha-2 receptor negative feedback, contributes to reduced sympathetic responsiveness in post-ischemic reperfused myocardium.

Cite This Study

Komatsu et al. (1991) studied this question.

synapsesocial.com/papers/6a97f5883de45e4adad7d226 https://doi.org/10.1253/jcj.55.900

Also Consider

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