Gas exchange and control of breathing in the electric eel, Electrophorus electricus

  title={Gas exchange and control of breathing in the electric eel, Electrophorus electricus},
  author={Kjell Johansen and Claude J. M. Lenfant and Knut Schmidt-Nielsen and Jorge A. Petersen},
  journal={Zeitschrift f{\"u}r vergleichende Physiologie},
Summary1.The electric eel Electrophorus electricus is an obligate air breather. Its mouth is structurally adapted for air breathing by an extensively diverticulated and richly vascularized oral mucosa. Air is regularly taken into the mouth and later expelled at the opercular openings. The present investigation concerns the respiratory properties of blood, the dynamics of gas exchange and the control of breathing in the electric eel.2.Fishes were anesthetized and catheters implanted for sampling… 

Respiratory gas exchange in the airbreathing fish, Synbranchus marmoratus

SynopsisThe partitioning of O2 uptake between aquatic and aerial gas exchange and its dependence on ambient water PO2 was studied in the facultative air breathing teleost Synbranchus marmoratus,

Gas exchange in the amphibious fish,Amphipnous cuchia

A high blood O2 capacity and O2 affinity and a high cardiac output reduce the efficiency loss and permit the fish to suspend with air breathing for up to 30 min with a modest reduction in arterial O2 saturation from near 90% to 60%.

The transition to air breathing in fishes. V. Comparative aspects of cardiorespiratory regulation in Synbranchus marmoratus and Monopterus albus (Synbranchidae)

The available cardiorespiratory data for air-breathing fishes indicate that the scope of air-inspiration tachycardia is smaller in lungfishes and other primitive species than in most teleosts.

Continuous measurement of oxygen tensions in the air-breathing organ of Pacific tarpon (Megalops cyprinoides) in relation to aquatic hypoxia and exercise

In normoxic water, tarpon rarely breathed air and apparently closed down ABO perfusion, indicated by a drop in ABO oxygen uptake rate to about 1% of that in hypoxic water and at a wide range of ABO PO2, suggesting that oxygen level in the ABO was not regulated by intrinsic receptors.

Control of the respiratory mode in air-breathing fishes

The transition from water breathing to air breathing for most bimodally breathing fishes appears to be critically dependent on sensory information from three major sets of peripheral receptors.

Control of cardiorespiratory function in response to hypoxia in an air-breathing fish, the African sharptooth catfish, Clarias gariepinus.

Acid-base and ion balance in fishes with bimodal respiration.

Air breathing in facultative air-breathing fishes is associated with an acid-base disturbance, resulting in an increased partial pressure of arterial CO2 and a reduction in extracellular pH (pHE); however, several fishes appear to be capable of tightly regulating tissue intracellular pH, despite a large sustained reduction in pHE, a trait termed preferential pHI regulation.

Effect of aerial O2 partial pressure on bimodal gas exchange and air-breathing behaviour in Trichogaster leeri

The observed increase in V̇O2/breath with increasing PO2,air was facilitated not only by an increase in apnoea duration but also by a increase in the air–blood PO2 gradient, indicating that ABO-PO2 is not regulated at a constant level by internal chemoreceptors.

Cardiac and respiratory responses in the climbing perchAnabas testudineus

The gas composition of the suprabranchial chambers has been measured and its relationship with the occurrence of an air breath, tachycardia and bradycardia is described.

Physiological consequences of prolonged aerial exposure in the American eel,Anguilla rostrata: blood respiratory and acid-base status

The results demonstrate that eels, unlike true amphibious fishes that utilize gills or buccal epithelia for gas transfer, are not particularly well-adapted for gas exchange in air but do display an unusual tolerance to hypoxemia.



Respiration in the African lungfish Protopterus aethiopicus. II. Control of breathing.

Respiratory and circulatory events were correlated during undisturbed breathing and during artificial lung inflation, and increased cardiac output and a shift in regional blood flow to a higher pulmonary flow occurred with air breaths.

Air breathing in the teleost Symbranchus marmoratus.

  • K. Johansen
  • Environmental Science
    Comparative biochemistry and physiology
  • 1966

Cardiovascular dynamics in the lungfishes

Cardiovascular dynamics and the functional status of a double circulation have been studied in representatives of the three genera of lungfishes; Neoceratodus, Lepidosiren, and Protopterus with a clear tendency for preferential circulation of oxygenated and deoxygenated blood.

Respiration in the African lungfish Protopterus aethiopicus. I. Respiratory properties of blood and normal patterns of breathing and gas exchange.

Gas analysis of blood samples drawn from unanaesthetized, free-swimming fishes attested to the important role of the lung in gas exchange and the high degree of functional in the circulation of oxygenated and deoxygenated blood.

The Reflex Co-ordination of the Heart Beat with Respiration in the Dogfish

Calculations from simultaneous records of the electrocardiogram and branchial blood pressure showed that heart beats originating near the time of mouth opening caused a rapid flow of blood through the gills at the time that water was expelled across them, and it was suggested that this synchronization of the periods of rapidflow of blood and water serves to maintain the diffusion gradient of oxygen across the gill epithelium.

Aortic blood flow in free-swimming elasmobranchs.

Respiratory adaptations in selected amphibians.

The reactions of fishes to gradients of dissolved atmospheric gases

The two species tried reacted negatively to a gradient of acetic acid in boiled water but some of the species did not react to ammonia in concentrations which produce death, and the carbon dioxide content of the water is probably the best single index of the suitability of theWater for supportng fishes.