Validity of Iodine Procedure of Histochemical Methods for Phosphorylase in Skeletal Muscle Fibers

Histochemical observations of glycogen synthetase activity using GDPG and TDPG as substrate in rat skeletal muscle fibers.

“…Based on the present light and electron microscopic observations, it is clear that different kinds of rat muscle fibers contained various enzyme activities which were reflected in different colors with iodine, and whose balance in relation to the enzyme probably resulted in size variants of the new glycogen according to the types of muscle fibers concerned as shown in the case of the phosphorylase reaction (12,13,14,18,22,(28)(29)(30). Although the characteristic glycogen synthesis occuring histochemically in the muscle fibers derived from the different nature of the enzyme itself, i.e.…”

HISTOCHEMICAL AND ELECTRON MICROSCOPIC OBSERVATIONS OF POLYGLUCOSE SYNTHESIZED BY ENZYMES IN THE SINO-ATRIAL NODAL CELL OF RABBITS TREATED WITH Β-Stimulating AND Β-Blocking AGENTS

“…In general, polyglucose stained bluish with iodine is synthesized by higher phosphorylase activity and polyglucose having a tendency to stain reddish is usually synthesized by both phosphorylase and higher branching glycosyltransferase activities (Takeuchi 1962) . According to Miyayama (1971Miyayama ( , 1972, iodine-blue stained polyglucose synthesized in white muscle fibers consists of amorphous aggregates or very smaller particles of new polysaccharide from 100 to 150 A in diameter, while iodine-red stained polyglucose histochemically synthesized in red muscle fibers is composed of larger particles of new polyglucose from 550 to 800 A in diameter. In their chemical, histochemical and physico-chemical investigations, Takeuchi et al, have suggested that the formation of various sizes of polyglucose may depend on the control of enzyme regulation of phosphorylase, branching glycosyltransferase and the related enzymes.…”

“…In their chemical, histochemical and physico-chemical investigations, Takeuchi et al, have suggested that the formation of various sizes of polyglucose may depend on the control of enzyme regulation of phosphorylase, branching glycosyltransferase and the related enzymes. (Iwamasa 1972, Miyayama 1971, Takeuchi 1958, 1962, 1974, Takeuchi et al 1955a, b, 1968a, b, 1974, 1975 In other words, the newly formed polyglucose particles reveal the enzyme actions in the localized regions, and it is important that there are some differences among new polyglucose particles in the localized regions.…”

Chemical Factors in the Iodine Coloration Reaction Employed in the Histochemical Demonstration of Phosphorylase

“…Swanson (31) previously pointed out that branching polyglucose showed a variable stainability according to the outer chain length of the a-1, 4-glucosidic bonds; polyglucose with longer outer chains was stained blue with iodine, and the a-D-glucopyranose series with shorter outer chains was stained red in the polyglucose-iodine complex. Miyayama (21) demonsstrated recently three types of polyglucose synthesized by phosphorylase which stained blue, violet and red with iodine respectively in an individual fiber of the rat skeletal muscle.…”

“…These newly synthesized polyglucoses were observed under the electron microscope, and differences among those polyglucoses were discussed (21,43). On the other hand, phosphorylase isoenzymes of the heart muscle were separated by Davis (6), Schliselfeld (26), Yunis (44), and Hanabusa (10).…”