Journal of Pharmacological and Toxicological Methods
Appraisal of state-of-the-artIsolated heart perfusion according to Langendorff—Still viable in the new millennium
Introduction
Only few isolated organ experimental models have been used as extensively as the isolated heart preparation according to Langendorff. It was first applied by physiologists, biochemists and morphologists for the study of heart biology. It was further applied by pharmacologists to test the effect of different cardiovascular drugs on the coronary vasculature, muscle contraction and heart rate. Today a variety of cardiovascular researchers still use this vital technique in myriad ways to investigate the heart, from the study of the effect of a single gene alteration on heart physiology, to novel therapeutic means to protect the heart from ischemia and other insults.
Although there are some limitations of the method including the absence of normal humoral influences and neuronal regulation, as well as high coronary flow and oedema when using cell free perfusate, the impact of these shortcomings is limited by the very advantage that much important first hand information can be gained by virtue of the elegant simplicity of this technique. Moreover, methods of recording some biophysical and biochemical parameters have been improved over the decades and the number of parameters we can now obtain using this method, the accuracy of these measurements, their high reproducibility and the relatively low costs predominate over the shortcomings, making this method a very useful tool in modern cardiovascular and pharmacological research.
This review will first provide a brief historical background of the method as well as details regarding organ isolation, perfusion solutions, set-ups for different modalities of perfusion, methods of recording various cardiovascular parameters and finally illustrate the utility of the isolated heart preparation according to Langendorff with a few select examples of recent research.
Section snippets
The isolated perfused frog heart
The isolated perfused mammalian heart preparation was developed on the basis of the isolated perfused frog heart. This method, widely used in the last part of the 19th century, was a starting point for the study of heart physiology. The scientist who deserves credit for first devising the isolated perfused frog heart preparation is Elias Cyon who established the method at the Carl Ludwig Institute of Physiology in Leipzig, Germany in 1866. For excellent reviews and original references in
General principle
Isolated perfused heart preparations nowadays are largely based on adaptations of the method originally described by Langendorff (Langendorff, 1898). The Langendorff heart preparation involves the cannulation of the aorta. The heart, once removed from a terminally anaesthetized animal, is held with forceps by the opened aortic root and is slipped over a fixed cannula on the perfusion apparatus. This cannula is attached to the outflow of a reservoir containing an oxygenated perfusion solution
Anaesthesia
Surgery on the animal requires general anaesthesia to be performed prior to the excision of the heart. Anaesthesia can be induced either by inhalation of volatile agents such as halothane or injection with barbiturates (Doring and Dehnert, 1987, Sutherland and Hearse, 2000). Ether should be avoided due to its ability to stimulate the sympathetic nervous system as well as its flammability. None of these methods are ideal for rendering an animal unconscious. Although both methods have their
Measurements
The isolated perfused heart preparation is extremely valuable for assessing the direct effects of drugs on contractile function, heart rate, coronary vascular tone, cardiac metabolism and electrical activity of the heart. In addition it may be utilized for morphological studies—hearts can be processed for examination by various microscopical techniques following microbiopsies or whole heart preparation and sectioning at the completion of the perfusion protocol. By switching the perfusate to one
Limitations of isolated heart perfusion
Limitations of the method include those mentioned above: lack of the normal humoral background and neuronal regulation of the heart, high coronary flow, vulnerability of the isolated heart to injury during instrumentation, increased possibility of preconditioning during instrumentation of the excised heart, higher oxidative stress, and deterioration of contractile function. Another criticism of isolated perfused heart studies is that, in addition to inducing a very simplistic form of ischemia
Specific applications of the method
The original Langendorff preparation underwent many modifications which permitted studies under numerous pathological conditions. Below, some of the possible applications of the method are described.
A few selected examples to illustrate that the method is thriving in the new millennium
The isolated perfused heart technique has evolved for over 100 years. Hardly any other procedure has resulted in such a great contribution to cardiovascular physiology and pharmacology and is still actively being used today as a valuable tool in cardiovascular research.
Conclusions
The isolated perfused heart according to Langendorff has served as a robust model for many fundamental discoveries in cardiac physiology, pathology and pharmacology for more than 100 years. Only few experimental models have enjoyed such an undiminished popularity over such a long time. It is still one of the most popular experimental designs in cardiovascular research and cardiovascular pharmacology. The disadvantages the model may suffer are outweighed by its benefits and the technique
Acknowledgements
Studies described here from R. Schulz were supported by grants from the Canadian Institutes for Health Research, the Heart and Stroke Foundation of Alberta, NWT and Nunavut and the Alberta Heritage Foundation for Medical Research (AHFMR). R. Schulz is an AHFMR Scientist.
M. Skrzypiec-Spring wishes to thank the University of Alberta for visiting fellowship support, and the Medical University of Wroclaw and the Foundation of the Medical University of Wroclaw for travel support. The study sponsors
References (75)
The Langendorff heart preparation—reappraisal of its role as a research and teaching model for coronary vasoactive drugs
Journal of Pharmacological Methods
(1979)- et al.
An improved perfusion apparatus for small animal hearts
Journal of Pharmacological Methods
(1986) - et al.
Sensitivity and specificity of isolated perfused guinea pig heart to test for drug-induced lengthening of QTc
Journal of Pharmacological and Toxicological Methods
(2004) - et al.
Experimental models for the study of cardiovascular function and disease
Pharmacological Research
(2000) - et al.
In vitro studies of human hearts
Annals of Thoracic Surgery
(2005) - et al.
Donor heart preservation with the potassium channel opener pinacidil: comparison with University of Wisconsin and St. Thomas' solution
Journal of Heart and Lung Transplantation
(2000) - et al.
New concepts in organ preservation
Transplant Immunology
(2002) - et al.
Transplantation of cryopreserved muscle cells in dilated cardiomyopathy: effects on left ventricular geometry and function
Journal of Thoracic and Cardiovascular Surgery
(2003) - et al.
Effect of nitric oxide synthase inhibition on the sympatho-vagal control of heart rate
Journal of the Autonomic Nervous System
(1998) - et al.
The isolated blood and perfusion fluid perfused heart
Pharmacological Research
(2000)