What is the clinical evidence from this study?

Study design: Other. Population: Isolated ventricular myocardium. Intervention: Dexmedetomidine. Primary outcome: Contractility, relaxation, and intracellular Ca2+ transients.

What question did this study set out to answer?

To evaluate the direct influence of the selective alpha 2-adrenoceptor agonist dexmedetomidine on mechanical contractility, relaxation, and intracellular calcium transients in isolated heart muscle.

November 1, 1990AnesthesiologyOpen Access

Effects of Dexmedetomidine on Contractility, Relaxation, and Intracellular Calcium Transients of Isolated Ventricular Myocardium

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Key result

Dexmedetomidine did not alter amplitude and time variables of twitches or intracellular Ca2+ transients in isolated ferret ventricular myocardium, suggesting no intrinsic myocardial contractile effects.

Why the study?

Does dexmedetomidine alter contractility, relaxation, and intracellular calcium transients in isolated right ventricular papillary muscles from reserpinized ferrets?

Population

Isolated right ventricular papillary muscles obtained from reserpinized ferrets

Design

Preclinical

Authors

PHPhilippe R. HousmansMayo Clinic in Arizona

Discussion

Member takes

Implication

Supports absence of direct inotropic effects preclinically; leaves open translation to human perioperative settings.

Key Points

To evaluate the direct influence of the selective alpha 2-adrenoceptor agonist dexmedetomidine on mechanical contractility, relaxation, and intracellular calcium transients in isolated heart muscle.
Examined isolated right ventricular papillary muscles obtained from reserpinized ferrets.
Measured isometric, isotonic, and zero-load-clamped twitches alongside intracellular calcium transients using aequorin across dexmedetomidine concentrations of 10⁻¹⁰ to 10⁻⁵ M.
Dexmedetomidine (10⁻¹⁰ to 10⁻⁵ M) caused no significant changes in twitch amplitude or timing variables, with only a slight increase in maximal isotonic relaxation rate at 10⁻⁵ M.
Intracellular calcium transients monitored with aequorin remained completely unchanged across dexmedetomidine concentrations from 10⁻⁸ to 10⁻⁵ M.

Structured PICO

Does dexmedetomidine alter contractility, relaxation, and intracellular calcium transients in isolated right ventricular papillary muscles from reserpinized ferrets?

Population

Isolated right ventricular papillary muscles obtained from reserpinized ferrets

Intervention

Dexmedetomidine (10(-10)-10(-5) M)

Outcome

Contractility, relaxation, and intracellular Ca2+ transientssurrogate

Dexmedetomidine has no intrinsic myocardial contractile effects in isolated ferret ventricular myocardium.

Cite This Study

Philippe R. Housmans (1990) studied Isolated ventricular myocardium. Dexmedetomidine was evaluated on Contractility, relaxation, and intracellular Ca2+ transients. Dexmedetomidine did not alter amplitude and time variables of twitches or intracellular Ca2+ transients in isolated ferret ventricular myocardium, suggesting no intrinsic myocardial contractile effects.

synapsesocial.com/papers/6a0de9d1cecdf5fb20baa549 https://doi.org/10.1097/00000542-199011000-00020

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Effects of Dexmedetomidine on Contractility, Relaxation, and Intracellular Calcium Transients of Isolated Ventricular Myocardium

Discussion

Member takes

Implication

Key Points

Structured PICO

Cite This Study

Effects of Dexmedetomidine on Contractility, Relaxation, and Intracellular Calcium Transients of Isolated Ventricular Myocardium

Discussion

Member takes

Implication

Key Points

Structured PICO

Cite This Study

Also Consider

Also Consider