What is the clinical evidence from this study?

Study design: Other. Intervention: Adenosine vs. Forskolin alone. Primary outcome: Left ventricular pressure and dP/dt.

What question did this study set out to answer?

The aim is to determine how adenosine influences the inotropic effects of forskolin in cardiac tissues.

May 1, 1986AJP Heart and Circulatory Physiology

Antagonism of forskolin effects by adenosine in isolated hearts and ventricular myocytes

View Full Paper

Ask AI

Bookmark

Key result

Adenosine antagonized the forskolin-induced increase in left ventricular pressure and dP/dt by 96 +/- 2% and 92 +/- 4%, respectively, in isolated perfused guinea pig hearts.

Population

Isolated perfused guinea pig hearts and isolated single ventricular myocytes

Comparison

Adenosine or its analogue N6-R-phenylisopropylade… vs Forskolin alone or dibutyryl cAMP

Design

Preclinical

Authors

GWG. Alexander WestHouston Methodist GIG IsenbergElectrophysiology LBLuiz BelardinelliElectrophysiology

Discussion

Member takes

Implication

Adenosine attenuates forskolin effects on contractility and Ca current in guinea pig preparations; leaves open mechanism and human in vivo relevance.

Key Points

The aim is to determine how adenosine influences the inotropic effects of forskolin in cardiac tissues.
Conducted experiments on isolated perfused guinea pig hearts (n=18) and isolated ventricular myocytes (n=10).
Administered forskolin and adenosine to assess changes in left ventricular pressure, dP/dt, action potentials, and calcium currents.
Used voltage-clamp techniques to measure calcium current in myocytes exposed to forskolin and adenosine.
Adenosine reduced the forskolin-induced increase in left ventricular pressure and dP/dt by 96% and 92%, respectively.
Forskolin caused a 39% increase in calcium current, which adenosine antagonized by 80%.
Increased concentrations of forskolin led to delayed after depolarizations, abolished by L-PIA.

Structured PICO

Population

Isolated perfused guinea pig hearts and isolated single ventricular myocytes.

Intervention

Adenosine (5 microM in hearts, 50 microM in myocytes) or its analogue N6-R-phenylisopropyladenosine (L-PIA)

Comparator

Forskolin alone (0.35 microM in hearts, 150 nM in myocytes) or dibutyryl cAMP

Outcome

Left ventricular pressure, dP/dt, action potential duration, calcium current, and sarcomere shorteningsurrogate

Adenosine strongly antagonizes the inotropic and electrophysiological effects of forskolin in isolated guinea pig hearts and ventricular myocytes, but not those of dibutyryl cAMP.

Cite This Study

West et al. (1986) studied this question. Adenosine vs. Forskolin alone was evaluated on Left ventricular pressure and dP/dt. Adenosine antagonized the forskolin-induced increase in left ventricular pressure and dP/dt by 96 +/- 2% and 92 +/- 4%, respectively, in isolated perfused guinea pig hearts.

synapsesocial.com/papers/6a6c10f5fd493d2318f4504e https://doi.org/10.1152/ajpheart.1986.250.5.h769

View Full Paper

Ask AI

Bookmark

Implication

Adenosine attenuates forskolin effects on contractility and Ca current in guinea pig preparations; leaves open mechanism and human in vivo relevance.

Antagonism of forskolin effects by adenosine in isolated hearts and ventricular myocytes

Discussion

Member takes

Implication

Key Points

Structured PICO

Cite This Study

Antagonism of forskolin effects by adenosine in isolated hearts and ventricular myocytes

Discussion

Member takes

Implication

Key Points

Structured PICO

Cite This Study

Also Consider

Also Consider