Intracellular localization and size of glycogen particles in glycogen synthesized under histochemical conditions.

Abstract

During the investigation of the histochemical synthesis of glycogen particles from glucose 1-phosphate by the phosphorylase-branching glycosyltransferase system in various tissue cells, it was observed that focal synthesis localized in a certain area of the cytoplasm occurred in some cells. This differed from the usual synthesis in which particles of similar size were synthesized within the cytoplasm. Otherwise, cytoplasmic particles of various size were also synthesized in other cells under the same histochemical condition. The possible significance of the presence of these patterns in glycogen synthesis is discussed.

Intranuclear Synthesis of Polyglucose Particles Under Histochemical Conditions in the Normal Rat

“…With regards to artificial synthesis of glycogen particles, Takeuchi (27) has pointed out that the newly formed polyglucose or glycogen particles appear to cause four patterns of the intracellular localization according to the cell type. Glycogen particles of a relatively similar size scattered within whole sarcoplasmic matrices among organelles are the first and most common pattern which is observed in many skeletal and cardiac muscle fibers.…”

Histochemical Observations on Polyglucoses Synthesized by Enzyme Activity in Cartilage Cells

“…Based on the above facts, it is suggested that the polyglucoses synthesized by enzyme activity under histochemical conditions in the cartilage cells consisted of shorter chains of a-1,4 glucosidic linkage in the outer chains of the macromolecules and were well branched with a-1,6 glucosidic linkages. Takeuchi and his co-workers (7,8,9,29,30,34,45) previously reported that the structure of the polyglucose particles histochemically synthesized by the enzyme activities of phosphorylase and branching glycosyltransferase is a macromolecular spherical branching body probably resembling the chemical structure proposed by French in 1964 (2). In the present study, the polyglucose particles histochemically synthesized in various cartilage cells revealed a rosette-like structure apparently similar to the spherical branching bodies of Takeuchi's results (41).…”

Characteristics of Polyglucose Particles Newlysynthesized by the Phosphorylase-Branching Glycosyltransferase System in Various Tissue Cells Under Histochemical Conditions

“…Actually, newly-formed polyglucoses synthesized from G 1-P by the PBG system revealed the characteristic coloration with iodine according to the kind of tissue cells. In the liver, the newly synthesized polyglucose particles appeared as rosette-like spheroidal branching bodies similar to the endogenous glycogen particles, which were usually stained reddish purple with iodine (17,33) . In the heart muscle, monoparticulates or rosary-like strings of beads stained purple with iodine could be synthesized by enzyme activity (15,29).…”

“…On the other hand, electron microscopic observation of polyglucose synthesized from glucose-l -phosphate by phosphorylase activity was first made by Sasaki and Takeuchi in human muscle fibers (18) . Since then, intracellular polyglucose synthesis has been studied in several kinds of tissue cells under the electron microscope (2,12,13,14,15,17,26,29,30,31,33). Takeuchi and his co-workers found that newly-formed polyglucose particles synthesized from glucose 1-phosphate (Gl-P) by the phosphorylase and branching glycosyltransferase system (PBG-system) under histochemical conditions varied in size, shape and electron-density according to the kind of tissue cells and that they were different from endogenous glycogen particles.…”