Mechanisms of Intracardiac Shunting in Reptiles

  • N. Heisler
Conference paper
Part of the Proceedings in Life Sciences book series (LIFE SCIENCES)

Abstract

Central vascular shunting (i.e., mixing of oxygenated blood returning from the lungs and of deoxygenated blood returning from the systemic tissues) is in higher vertebrates (birds, mammals) generally a feature of a pathological status and considered as a factor of inefficiency, whereas in amphibians and noncrocodilian reptiles the incompletely divided ventricle system implies intracardiac shunting also during the physiological status. The intriguing questions evolving have stimulated numerous studies already during the last century, which were primarily concerned with anatomical description and functional analysis of reptilian hearts and central vessel system, and resulted often in extremely contradictory conclusions (e.g., Brücke 1852; Goodrich 1916, 1919, 1930; Greil 1903; Benninghof 1933; Hopkinson and Pancoast 1937; Mahandra 1942; Mathur 1944, 1946; Mertens 1942; O’Donoghue 1918; Rathke 1857; Thapar 1924; Vorstman 1933). More recent studies utilizing physiological techniques (see below) resulted in similarly conflicting results between the two extremes of no shunting at all, and shunting to a large extent in both directions (L → R, R → L, or both simultaneously).

Keywords

Catheter Sludged Respiration Dextran Washout 

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Copyright information

© Springer-Verlag Berlin Heidelberg 1985

Authors and Affiliations

  • N. Heisler
    • 1
  1. 1.Abteilung PhysiologieMax-Planck-Institut für Experimentelle MedizinGöttingenGermany

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