Changes In Glycogen Content Research Articles

HISTOCHEMICAL AND QUANTITATIVE CHANGES IN GLYCOGEN AND PHOSPHORYLASE DURING DISUSE ATROPHY OF THE PIGEON PECTORALIS.

Histochemical and quantitative biochemical changes in glycogen content and phosphorylase activity of pigeon breast muscle were studied during development of disuse atrophy from one day to sixty days. Of the two types of muscle fibers present in the pigeon breast muscle the large white glycogen-loaded fibers, which are well adapted for an anaerobic metabolism, were found to lose their glycogen store and phosphorylase activity during the early days of atrophy. On the other hand, the smaller, red, fat-loaded fibers, which are well adapted for an aerobic metabolism, were found to acquire more glycogen and phosphorylase activity during the same period. The staining reaction of these fibers for phosphorylase thus, as with biochemically different branching enzymes, presented a mosaic. However, a few small fibers showed no increase in glycogen content or phosphorylase activity. The histochemical observations also revealed that the majority of the large white fibers were reduced in size, filled with fat, and separated by connective tissue during the later stages of atrophy. Fibers of this sort disappeared or were completely engulfed by connective tissue. Very few small fibers changed in this way. In certain regions an entire fasciculus containing both types of fiber was found to be replaced by fat and connective tissue, leaving a few narrow red fibers intact. There was no phosphorylase activity in the connective tissue. The quantitative studies showed a decrease in glycogen and phosphorylase levels in the muscle early in disuse. After 60 days of atrophy the phosphorylase level recovered somewhat but the glycogen level remained low.

Developmental changes in glycogen content of primordial germ cells in chick embryo.

SummaryGlycogen containing tissue PGCs on the 2nd day of incubation appeared first in the splanchnic mesoderm posterior to the omphalomesenteric arteries. These cells originated from smaller circulating PGCs which contained less glycogen. The PGCs moved out of the capillaries, enlarging and accumulating glycogen as they did so, and migrated to the gonadal site. As these cells became located in the developing gonad they lost their glycogen. This loss of glycogen became evident on the 4th day, was marked on the 5th and by the 7th the majority were without glycogen.

Effect of hyperglycemia and hypoglycemia on the glycogen content of the pituitary and adrenal glands of normal, subdiabetic and diabetic rats.

The glycogen content of pituitary, adrenal and thyroid tissue of alloxandiabetic and normal rats was determined. An increased glycogen content was found in these endocrine glands in the diabetic rats. The pituitary glycogen content appeared to reflect the blood sugar level. When the blood sugar of normal, subdiabetic and diabetic rats was elevated by massive injections of glucose, the pituitary glycogen content was increased moderately. When the blood sugar of diabetic rats was lowered by insulin injection, the pituitary glycogen content decreased; however, this change in glycogen content often lagged behind the blood sugar changes. By contrast, the adrenal glycogen content did not reflect the blood sugar level; when the blood sugar was decreased by insulin treatment (in the diabetic rat) or elevated by glucose administration (in both normal and diabetic rats), the adrenal glycogen content was decreased. The possible mechanisms by which hyper- and hypoglycemia affect the glycogen content of the endocrine ...

Glycogenic effect of formaldehyde as related to the adrenal cortex.

Liver glycogen concentration was measured in fasting intact, adrenalectomized and cortisone-treated adrenalectomized rats 24 hours after subcutaneous injection of 1.5% formaldehyde. Formaldehyde caused an elevation in liver glycogen in intact rats fasted for 48 hours before the animals were killed. There was no change in glycogen concentration after formaldehyde in fasting adrenalectomized rats maintained only on 0.9% NaCl or given, in addition, 0.75 mg/ day cortisone acetate for 9 days. Formaldehyde failed to have a statistically significant effect on liver glycogen in intact rats that were fasted only 24 hours before sacrifice. In the control groups of the intact and the cortisone-treated adrenalectomized rats, liver glycogen levels were much higher after a 48- hr fast than after a 24-hr fast. Length of fast did not influence liver glycogen in untreated adrenalectomized rats.

Effect of ACTH on glucose metabolism in rat adrenal in vitro.

Quartered rat adrenals were incubated in vitro with glucose-1-C14, glucose- 6-C14 and glucose-U-C14. The oxidation of glucose-l-Cu to CO2 was 1.3 times that of glucose-6-C14. ACTH increased the oxidation of all 3 labeled glucose molecules by 20%, and there was no change in the C-l:C-6 ratio. ACTH increased 4- to 6-fold the concentration of corticosterone in the medium. The glucose carbon incorporation into total lipid was not affected by ACTH, and the C-l:C-6 ratio remained unchanged. ACTH decreased glucose-C14 incorporation into glycogen, but no change in glycogen content was noted. In vivo administration of ACTH also failed to decrease the adrenal glycogen content. These observations do not support the importance of phosphorylase activation or of metabolism via the hexose monophosphate pathway in ACTH-stimulated steroidogenesis.

Comparative histochemical data on glycogen changes in x-ray and strontium-90 radiation sickness

A histochemical study was made of the glycogen content in the liver, cardiac muscle and lungs of rabbits at the initial period of chronic radiation sickness provoked by the intravenous injection of strontium-90 in the dose of 0.5 μC per g of body weight. An essential difference was noted in the character of the initial changes of glycogen content in radiation sickness caused by the irradiation with x-rays and strontium-90. In the first case the changes in the glycogen content may be explained by the functional disturbances, whereas in the second-by more profound derangements in the carbohydrate metabolism. At the height of the disease the cause of reduced glycogen content is the same, and, according to the authors' data, is to a certain extent connected with the increased activity of alkaline glycerophosphatase.

Postmortem Changes in Glycogen Content of Human Eccrine Sweat Glands

Postmortem Changes in Glycogen Content of Human Eccrine Sweat Glands

Effect of Cortisone and X-radiation on RNA and Glycogen Content of Rat Hepatocytes.

Rats were treated with cortisone, x radiation and both agents in combination, and the effects noted on RNA and glycogen content of liver. Under various conditions of treatment, RNA content incrsased promptly to different degrees and returned to normal values at different times. Comparison of RNA content/liver in the present study, with those of DNA/nucleus in previous study, indicates that, in animals which received cortisone alone, the maximum increase in RNA was obtained 24 hours prior to a fali in concentration of DNA. However, accumulation of RNA in rats which received x-radiation or both cortisone and x- radiation was 48 hours earlier than when the fall of DNA became significant. X radiation or cortisone administration caused glycogen accumulation in liver, the former transiently, the latter in more dramatic and prolonged manner. X radiation, prior to administration of cortisone, modified the response and decreased glycogen accumulation. Changes in glycogen content in contradistinction to RNA could not be correlated with those of DNA. (auth)

Effect of hyperthyroidism on glycogen content of the isolated rat liver.

A method is described for determining net changes in glycogen content of the isolated rat liver after 6 hours of perfusion using the glycogen content of the caudate lobe of the liver as a control value. A series of experiments was performed in which livers obtained from normal and hyperthyroid rats were perfused at low and high perfusate glucose levels and the glycogen content of the livers was determined before and after perfusion. It was found that the isolated liver from the untreated rat under artificial perfusion neither increases nor decreases appreciably in glycogen concentration during a period of six hours at either low or high glucose perfusate concentrations. In contrast, the isolated hyperthyroid rat liver, which is uniformly low in glycogen concentration, effects a marked increase in its glycogen concentration by the end of perfusion at high perfusate glucose concentration (above 600 mg.%). It was concluded that the data confirm the effect of thyroxine in depleting the liver of its glycogen content, and establishes that thyroxine-influences the metabolism of the hyperthyroid liver and its enzyme systems in promoting glycogen storage even in the presence of increased glucose metabolism.

Histochemical Studies of Human Skin Autografts and Homografts

Summary o 1.Glycogen and ribonucleic acid have been studied histochemically in serial biopsies of human skin autografts and homografts. 2.During the latent phase before homograft destruction the epithelium of homografts and autografts shows similar changes in glycogen and ribonucleic acid content. 3.There is no major change in glycogen content of homograft epidermis prior to destruction. 4.The homogeneous polysaccharide-containing component of the basement membrane between epidermis and dermis appears unchanged at the time of destruction of the epidermis. 5.The possible role of ribonucleoprotein in the mechanism of homograft destruction is discussed.

Histochemical studies of human skin autografts and homografts

Summary o 1.Glycogen and ribonucleic acid have been studied histochemically in serial biopsies of human skin autografts and homografts. 2.During the latent phase before homograft destruction the epithelium of homografts and autografts shows similar changes in glycogen and ribonucleic acid content. 3.There is no major change in glycogen content of homograft epidermis prior to destruction. 4.The homogeneous polysaccharide-containing component of the basement membrane between epidermis and dermis appears unchanged at the time of destruction of the epidermis. 5.The possible role of ribonucleoprotein in the mechanism of homograft destruction is discussed.

The Biologic Characteristics of the Normal Vagina

Summary 1. Extensive studies were made on the vaginal tract of more than 500 patients; included in this number were 37 normal patients in whom the studies were made three times weekly through one to three menstrual cycles. The special studies made included determinations of the pH of the vaginal mucosa, cytologic studies of vaginal. smears, examination of smears stained for glycogen content, determination of the bacterial flora, and the study of vaginal biopsies. 2. The role of the estrogens as the major factor in controlling the histologic and cytologic features of the vaginal epithelium is reviewed, but evidence indicating that progesterone and perhaps other steroid hormones have an important influence is presented. Certain cyclic histologic changes were frequently noted on the biopsies, but in the main these were not nearly so clear-cat as the changes noted from cytologic study of vaginal smears. 3. Present evidence indicates that the estrogens are the dominant factor in causing the mobilization of glycogen in the vaginal epithelium; progesterone may aid in this process. Androgens appear to be an inhibiting factor in glyconeogenesis. Glycogen is abundantly present in vaginal biopsies. A concentration of 2.5 to 3.0 mg. per cent was encountered in the upper part of the vagina and smaller concentrations in the lower part of the vagina. The metabolism of vaginal glycogen is not known, but various theories are discussed. Vaginal biopsies prepared with Best's carmine stain were found to be highly suitable for demonstrating distribution of vaginal mucosa. Cyclic changes in glycogen content were far more easily noted in vaginal smears stained by an iodine method. It was found that the glycogen content of the superficial vaginal epithelium showed a tendency to increase throughout the cycle and then to fall in the late premenstrual phase, thus roughly approximating the estrogen excretion through the cycle. 4. The various methods for determining the pH of the vaginal secretion and mucosa are reviewed. Direct determination of the pH of the vaginal mucosa by the glass electrode method was chosen as most accurate and reliable. A special glass electrode is described which has been found to be highly satisfactory for this purpose. In making 632 readings on 100 normal women, it was found that the pH varied from 4.0 to 5.0 in all except 3 per cent of the determinations. A pH gradient was found to exist in the vagina in most patients. The highest acidity was generally encountered in the anterior fornix. The next highest readings were obtained in the middle third of the vagina; these were generally quite constant and most nearly approximated the pH of the vaginal secretion. Lower values were obtained in the lower third of the vagina, while determinations made in the posterior fornix usually varied considerably. In the 37 cases studied at frequent intervals, a periodic variation in pH was observed in many instances. The average readings indicate that pH gradually falls to reach its lowest point at the midcycle and then gradually rises to meet the highest values at the premenstrual stage. 5. The factors which influence the character of the vaginal flora are discussed. From available evidence it would appear that the vaginal pH is the strongest immediate factor determining the type of organisms present in the vaginal tract. The vaginal pH and flora were correlated for a large series of patients and indicated that most of the patients with Grade I flora had a vaginal pH of 3.9 to 5.0 (range 3.9 to 6.0, average 4.56). Majority of patients with a Grade II flora-fell in the pH interval 4.6 to 5.5 (range 4.0 to 7.0, average 5.09). In Grade III type the majority of the patients had a pH of 5.1 to 6.0 (range 4.0 to 9.0, average 5.54).