What does this research mean for the field?

Acetylcholine predominantly activates a potassium conductance in guinea-pig atrial cells, and the superimposition of this relaxing outward potassium current can lead to an overestimation of acetylcholine's inhibitory effect on calcium currents. Novelty: ClaimNovelty.INCREMENTAL. Consensus alignment: ConsensusAlignment.NEUTRAL.

What question did this study set out to answer?

Investigate the ionic currents and the effects of acetylcholine on isolated guinea-pig atrial cells.

February 1, 1985The Journal of PhysiologyOpen Access

Membrane currents and their modification by acetylcholine in isolated single atrial cells of the guinea‐pig.

View Full Paper

Ask AI

Bookmark

Population

Isolated single atrial cells of the guinea-pig heart

Comparison

Acetylcholine at doses ranging from 10 M to 10 M vs Control (baseline/absence of ACh)

Design

Preclinical

Authors

TIToshio IijimaTohoku University HIHiroshi IrisawaDokkyo Medical University MKMasaki KameyamaShinshu University

Discussion

Member takes

Implication

ACh K+ activation may confound atrial iCa assays; leaves open direct Ca2+ effects across species or preparations.

Key Points

Investigate the ionic currents and the effects of acetylcholine on isolated guinea-pig atrial cells.
Patch-clamp technique used for whole-cell recordings
Voltage-clamp experiments assessed various ionic currents
Dose-response evaluation of acetylcholine effects on membrane potential and currents
Acetylcholine significantly shortened action potential duration in a dose-dependent manner (max effect at 10(-6) M)
K+ currents increased with ACh administration, showing progressive deactivation with a time constant of 111 +/- 16 ms
ACh influenced Ca2+ current reduction, which remained insignificant in Cs+-loaded cells at 10(-7) M ACh

Structured PICO

Population

Isolated single atrial cells of the guinea-pig heart

Intervention

Acetylcholine (ACh) at doses ranging from 10(-9) M to 10(-5) M

Comparator

Control (baseline/absence of ACh)

Outcome

Membrane potential and ionic currents (Ca2+ current, inward and outward rectifying K+ currents)surrogate

In guinea-pig atrial cells, acetylcholine predominantly activates a K+ conductance, which can confound the measurement of its effects on calcium currents.

Cite This Study

Iijima et al. (1985) studied this question.

synapsesocial.com/papers/6a1bf8811567d2fc4d5f592e https://doi.org/10.1113/jphysiol.1985.sp015598

View Full Paper

Ask AI

Bookmark

Membrane currents and their modification by acetylcholine in isolated single atrial cells of the guinea‐pig.

Discussion

Member takes

Implication

Key Points

Structured PICO

Cite This Study

Membrane currents and their modification by acetylcholine in isolated single atrial cells of the guinea‐pig.

Discussion

Member takes

Implication

Key Points

Structured PICO

Cite This Study

Also Consider

Also Consider