Glycogen content of the various parts of the dog heart using desoxyribonucleic acid as a reference standard

ABSTRACT

Comparison of the metabolic activity of the various cardiac tissues is liable to error if the activity is expressed on the basis of wet weight as is usually done. This is because of the varying amounts of fibrous tissue in the various cardiac tissues, especially in the false tendons which is taken as representative of Purkinje tissue. The use of desoxyribonucleic acid as a reference standard for tissue analysis was suggested by the work of Bolvin, Vendrely & Vendrely (1948) and for metabolic experiments by the work of Gray & Deluca (1956). The amount of DNA per nucleus in different somatic tissues of a species is constant and from the DNA content of a given mass of tissue the number of cells in it can be calculated. The metabolic activity is then expressed on a per cell basis. In this work, the above method has been modified taking into consideration the fibrous content of the tissue samples, and has been applied to the determination of glycogen in cardiac tissues.