Comparative ultrastructure of cardiac cell membrane specializations. A review

doi:10.1016/0002-9149(70)90578-3

The American Journal of Cardiology

Volume 25, Issue 2, February 1970, Pages 184-194

https://doi.org/10.1016/0002-9149(70)90578-3 Get rights and content

Abstract

Among animal hearts, there are many differences in the anatomic features of various myocardial cells, the occurrence of junctional complexes joining adjacent cells, the geometry of apposition of cells forming bundles of fibers, and the form and extent of specializations of intracellular membrane systems. The working fibers of chicken and frog hearts, which have no transverse tubules, are considerably smaller in diameter than those of their mammalian counterparts, which do have such tubules. Purkinje fibers in the hearts of small mammals differ in structure and appositional geometry from those of the larger mammals, and again from those of the chicken. All Purkinje fibers lack transverse tubules. Focal specializations of the sarcoplasmic reticulum, the junctional sarcoplasmic reticulum, are prominent in chicken and mammalian, but not in frog cardiac muscle. Gap junctions are frequent in mammalian hearts, but seem to be rare, small or absent altogether in both frog and chicken hearts.

References (13)

JR Sommer et al.
Cardiac muscle. A comparative study of Purkinje fibers
J Cell Biol
(1968)
JR Sommer et al.
Cardiac muscle. A comparative ultrastructural study with special reference to frog and chicken hearts
Z Zellforsch
(1969)
WG Forssmann et al.
Untersuchungen zur Ultrastruktur des Rattenherzmuskels mit besonderer Beruecksichtigung des sarkoplasmatischen Retikulums
Z Zellforsch
(1966)
FO Simpson et al.
The relationship between the transverse tubular system and other tubules at the Z disc level of myocardial cells in the ferret
Amer J Anat
(1968)
MM Dewey et al.
A study of the structure and distribution of the nexus
J Cell Biol
(1964)
EA Johnson et al.
A strand of cardial muscle
J Cell Biol
(1967)

There are more references available in the full text version of this article.

Cited by (73)

The cardiovascular system
2022, Sturkie's Avian Physiology
Birds have evolved a tightly controlled cardiovascular system that meets the rigorous energetic demands of flight. The bird heart has a functional anatomy similar to that of the mammalian heart with four chambers and an extensive coronary circulation. The electrical conducing system of the avian heart includes a sinoatrial node, atrioventricular (AV) node, AV Purkinje ring, and the bundle branches. The vascular system is composed of arteries, capillaries, and veins and includes a pair of ductus arteriosi as embryos. Control of cardiovascular function includes both cardiac and the vasculature limbs. Peripheral vasculature reactivity is regulated by local mechanical autoregulation, humoral factors, and the autonomic nervous system altering vascular resistance. Humoral factors that regulate vascular resistance include pH, CO₂, nitric oxide, angiotensin II, and circulating catecholamines. Both sympathetic and parasympathetic inputs have important roles in regulating the vasculature and the heart function. Sympathetic control of the cardiac function increases both contractile force and heart rate. Parasympathetic control affects cardiac contractile force and heart rate at the pacemaker and conducting tissues. Cardiac output is regulated by chemoreflexes and baroreflexes. All of these regulatory pathways mature late in embryonic life, providing fine control by the time of hatch. Finally, the avian cardiovascular system has evolved to function effectively during long migration flights, some at high altitude and during diving.
The Cardiovascular System
2015, Sturkie's Avian Physiology: Sixth Edition
Birds have evolved a high-performance cardiovascular system to meet the rigorous demands of running, flying, swimming, or diving in a variety of environments, some of them extreme. Sustained high levels of activity in these environments place severe demands on the cardiovascular system to provide adequate delivery of oxygen to working vascular beds and to provide efficient removal of metabolic products. Furthermore, birds are endothermic organisms and the cardiovascular system plays a major role in conserving or removing body heat. The descriptions of the component parts of the circulatory system in this chapter illustrate that these transport requirements are met in a variety of ways in birds inhabiting particular environmental niches. This chapter describes the morphological and functional aspects of the avian heart, circulatory hemodynamics, and the vascular tree. A common thread running through this discussion is that the component parts of the circulation must function in an integrated fashion to ensure tissue oxygen delivery matches tissue demands. This is accomplished through the integrative control of circulation by autoregulatory, humoral, and neural mechanisms. Since the last edition of this book, a significant number of studies have examined the development of cardiovascular control in avian embryos which has expanded our understanding of this system throughout ontogeny. Finally, this chapter examines how the cardiovascular system functions within a complex animal, interacting in complex environments.
Effect of nonuniform interstitial space properties on impulse propagation: A discrete multidomain model
2008, Biophysical Journal
Citation Excerpt :
Table 2 summarizes the simulation results of the discrete multidomain for increasing asymmetry ratios from 1:10 to 1:500 or 1:1000 as a percent change from the simulated bidomain value. The limiting asymmetry case was reached when the narrow interstitial depth diminished to 2 nm, the smallest membrane apposition experimentally observed (17). The results show that for moderate extracellular distributions where the surrounding extracellular depth was >50 nm, the bidomain and asymmetric discrete multidomain models predict similar potentials and conduction velocities.
This work presents a discrete multidomain model that describes ionic diffusion pathways between connected cells and within the interstitium. Unlike classical models of impulse propagation, the intracellular and extracellular spaces are represented as spatially distinct volumes with dynamic/static boundary conditions that electrically couple neighboring spaces. The model is used to investigate the impact of nonuniform geometrical and electrical properties of the interstitial space surrounding a fiber on conduction velocity and action potential waveshape. Comparison of the multidomain and bidomain models shows that although the conduction velocity is relatively insensitive to cases that confine 50% of the membrane surface by narrow extracellular depths (≥2 nm), the action potential morphology varies greatly around the fiber perimeter, resulting in changes in the magnitude of extracellular potential in the tight spaces. Results also show that when the conductivity of the tight spaces is sufficiently reduced, the membrane adjacent to the tight space is eliminated from participating in propagation, and the conduction velocity increases. Owing to its ability to describe the spatial discontinuity of cardiac microstructure, the discrete multidomain can be used to determine appropriate tissue properties for use in classical macroscopic models such as the bidomain during normal and pathophysiological conditions.
Atrioventricular conduction in mammalian species: Hemodynamic and electrical scaling
2005, Heart Rhythm
The purpose of this study was to investigate scaling of the duration of late diastolic left ventricular (LV) filling in relation to AV conduction time (delay) (PR interval on the ECG) in mammals.
From mouse to whale, AV delay increases 10-fold, whereas body mass increases one million-fold. The apparent “mismatch” results from scaling of AV delay versus body and heart mass.
We measured (1) mitral orifice diameter in 138 postmortem hearts of 48 mammalian species weighing between 17 g and 250 kg and (2) transmitral diastolic flow using magnetic resonance imaging (MRI) recordings of 10 healthy human individuals. (3) We visually inspected early and late diastolic LV filling. (4) We developed two physical models to explain scaling of late diastolic LV filling time.
(1) Diameter of the mitral orifice proportionally relates to heart length (third root of heart mass). (2) Atrial contraction starts at a fixed instant (± 80%) of the (normalized) cardiac cycle and contributes 31% ± 5% to LV filling. (3) MRI shows that during diastole, the left atrium (LA) and LV form a single space. (4) The physical models relate the duration of late diastolic LV filling directly to heart length, the third root of heart mass.
(1) Late diastolic (LV) filling time scales with heart length (third root of heart mass). (2) No “mismatch” exists between AV delay and heart size. (3) Knowledge of the actual starting time of atrial contraction may contribute to better treatment of patients with heart failure. (4) The findings suggest that in evolution of mammalian species, hemodynamics commands electrical behavior of the heart.
The Sisyphean task of atrioventricular nodal scaling: Is the stone at the top of the mountain?
2005, Heart Rhythm
Control of apoptosis by IP<inf>3</inf> and ryanodine receptor driven calcium signals
2000, Cell Calcium
Intracellular calcium signals mediated by IP₃and ryanodine receptors (IP₃R/RyR) play a central role in cell survival, but emerging evidence suggests that IP₃R/RyR are also important in apoptotic cell death. Switch from the life program to the death program may involve coincident detection of proapoptotic stimuli and calcium signals or changes in the spatiotemporal pattern of the calcium signal or changes at the level of effectors activated by the calcium signal (e.g. calpain, calcineurin). The fate of the cell is often determined in the mitochondria, where calcium spikes may support cell survival through stimulation of ATP production or initiate apoptosis v ia opening of the permeability transition pore and release of apoptotic factors such as cytochrome c. The functional importance of these mitochondrial calcium signalling pathways has been underscored by the elucidation of a highly effective, local Ca²⁺coupling between IP₃R/RyR and mitochondrial Ca²⁺uptake sites. This article will focus on the IP₃R/RyR-dependent pathways to apoptosis, particularly on the mitochondrial phase of the death cascade.

View all citing articles on Scopus

^☆: This work was supported in part by a grant-in-aid (66 737) from the American Heart Association and by Grant HE 12486-01 from the National Institutes of Health.

View full text

Symposium development and ultrastructure of the embryonic heart. Part oneComparative ultrastructure of cardiac cell membrane specializations. A review☆

Abstract

Cardiac muscle. A comparative study of Purkinje fibers

J Cell Biol

Cardiac muscle. A comparative ultrastructural study with special reference to frog and chicken hearts

Z Zellforsch

Untersuchungen zur Ultrastruktur des Rattenherzmuskels mit besonderer Beruecksichtigung des sarkoplasmatischen Retikulums

Z Zellforsch

The relationship between the transverse tubular system and other tubules at the Z disc level of myocardial cells in the ferret

Amer J Anat

A study of the structure and distribution of the nexus

J Cell Biol

A strand of cardial muscle

J Cell Biol

Symposium development and ultrastructure of the embryonic heart. Part one
Comparative ultrastructure of cardiac cell membrane specializations. A review☆