Synapse
⌘+K
Synapse
PulseExploreClubsResearchersJournals
Instagram
HomeClubsExplore
January 1, 1961The Journal of General PhysiologyOpen Access

Investigations of the Electrical Properties of Cardiac Muscle Fibres with the Aid of Intracellular Double-Barrelled Electrodes

View Full Paper
Ask AI
Bookmark
Share

Population

Isolated rabbit right ventricle muscle fibres

Design

Preclinical

Authors

EJEdward A. JohnsonUniversity College LondonJTJ. TilleMonash University

Discussion

Loading...

Member takes

Implication

Distinguishes P versus V fibre properties in rabbit ventricle; leaves open translational relevance to human electrophysiology.

Key Points

  • Investigate the membrane electrical properties and action potential responses of distinct cardiac muscle fibre types in the isolated rabbit right ventricle.
  • Delivered intracellular currents to isolated rabbit right ventricle muscle fibres using double-barrelled microelectrodes.
  • Assessed changes in action potential amplitude during the rising phase under varying intensities of hyperpolarising current.
  • Calculated mean resting polarisation resistance and rheobase current strength across identified fibre categories.
  • Identified two distinct fibre types (P and V); P fibres displayed a linear relationship between hyperpolarising current and action potential amplitude, whereas V fibres showed negligible change until reaching a threshold current.
  • P fibres exhibited an estimated mean resting polarisation resistance of (106 ± 13) kΩ and a rheobase current strength of (0.08 ± 0.02) µA.
  • V fibres exhibited an estimated mean resting polarisation resistance of (47 ± 29) kΩ and a higher rheobase current strength of (0.47 ± 0.28) µA.

Structured PICO

P
Population
Isolated rabbit right ventricle muscle fibres
I
Intervention
Application of hyperpolarising current via intracellular double-barrelled microelectrodes
O
Outcome
Relation between hyperpolarising current intensity and maximum amplitude of action potential, resting polarisation resistance, and rheobase current strengthsurrogate

This basic science study identifies two distinct types of cardiac muscle fibres (P and V) in the rabbit right ventricle based on their electrophysiological responses to hyperpolarising currents.

Cite This Study

Johnson et al. (1961) studied this question.

synapsesocial.com/papers/6a7d0b1aab1caed3bf748ffehttps://doi.org/10.1085/jgp.44.3.443
View Full Paper
Ask AI
Bookmark
Share

Also Consider

Synapse has enriched 2 closely related papers on similar clinical questions. Consider them for comparative context:

  1. 1An Instrument for the Production of Microelectrodes Used in Electrophysiological Studies1953 · 82 citations
  2. 2A quantitative description of membrane current and its application to conduction and excitation in nerve1952 · 23,558 citations