The Experts below are selected from a list of 792 Experts worldwide ranked by ideXlab platform
Keiichi Ohya - One of the best experts on this subject based on the ideXlab platform.
-
Osteoporosis-like changes in Walker Carcinoma 256-bearing rats, not accompanied with hypercalcemia or parathyroid hormone-related protein production.
Japanese Journal of Cancer Research, 1995Co-Authors: Yoshihiro Waki, Kenichi Miyamoto, Shohei Kasugai, Keiichi OhyaAbstract:Walker Carcinoma 256 (W256) was reported to induce hypercalcemia dependent on bone metastasis and/or parathyroid hormone-related protein (PTHrP) in the rat, providing a model of the humoral hypercalcemia of malignancy. In this study, after the subcutaneous inoculation of cells of the W256/S line, which is maintained in this laboratory, into young female Wistar Imamichi rats (6 weeks old), serum calcium and phosphorus levels changed only within the control range, whereas serum alkaline phosphatase activity and urinary calcium level significantly increased and urinary phosphorus decreased during the tumor growth, resulting in hypercalciuria and hypophosphaturia. W256/S did not express PTHrP-mRNA, whereas LLC-W256 cells did express it. Serum PTHrP level was not changed in W256/S-bearing rats. Osteoporosis-like changes, bone weight loss, low contents of bone calcium and phosphorus, and a decrease in the bone mineral density (BMD), were observed in the femur 14 days after the tumor inoculation. There was a pronounced decrease in the serum 17β-estradiol level during the tumor growth. The reduction of BMD of femurs in W256/S-bearing rats was significantly inhibited by treatment with salmon calcitonin or 17β-estradiol. On the basis of these results, W256/S Carcinoma-bearing rats seem to be a useful model for osteoporosis of hypoovarianism.
N A Krajushkina - One of the best experts on this subject based on the ideXlab platform.
-
Tissue distribution of rat macroglobulins in tumour‐bearing rats
International Journal of Experimental Pathology, 2001Co-Authors: N V Mingaljev, N A KrajushkinaAbstract:Rat macroglobulins were determined in blood sera and extracts of tissues of intact rats and rats with Walker Carcinoma by rocket immunoelectrophoresis. The serum levels of alpha1-macroglobulin (alpha1MG) alpha2-macroglobulin (alpha2MG) and pregnancy-associated alpha1-glycoprotein (alpha1PAG) were 1.86 +/- 0.07 mg/ml, 0.12 +/- 0. 02 mg/ml and 18.32 +/- 4.07 AU/ml respectively in control rats. Maximum concentrations of alpha1MG were found in heart, lung and spleen and lesser quantities were in liver and thymus, while alpha2MG and alpha1PAG were not found at all in tissue extracts from control rats. Serum alpha2MG and alpha1PAG concentrations increased more than 30-fold in tumour-bearing rats compared to control animals, while alpha1MG serum concentration was little changed. Increases in all three macroglobulins occurred in the tissues of tumour-bearing rats, particularly alpha1PAG. The tissue concentrations of alpha1MG and alpha2MG were similar and the tissue distribution was also similar with highest concentrations in heart and lung. Considerable quantities of the proteins were found in the tumour and part of peritoneum which made contact with the tumour. Changes in the protein concentrations in serum and tissue extracts of tumour-bearing rats suggest that all members of rat macroglobulin family are disturbed during the development of the Walker Carcinoma, though only alpha2MG and alpha1PAG were substantially elevated.
Yoshihiro Waki - One of the best experts on this subject based on the ideXlab platform.
-
Osteoporosis-like changes in Walker Carcinoma 256-bearing rats, not accompanied with hypercalcemia or parathyroid hormone-related protein production.
Japanese Journal of Cancer Research, 1995Co-Authors: Yoshihiro Waki, Kenichi Miyamoto, Shohei Kasugai, Keiichi OhyaAbstract:Walker Carcinoma 256 (W256) was reported to induce hypercalcemia dependent on bone metastasis and/or parathyroid hormone-related protein (PTHrP) in the rat, providing a model of the humoral hypercalcemia of malignancy. In this study, after the subcutaneous inoculation of cells of the W256/S line, which is maintained in this laboratory, into young female Wistar Imamichi rats (6 weeks old), serum calcium and phosphorus levels changed only within the control range, whereas serum alkaline phosphatase activity and urinary calcium level significantly increased and urinary phosphorus decreased during the tumor growth, resulting in hypercalciuria and hypophosphaturia. W256/S did not express PTHrP-mRNA, whereas LLC-W256 cells did express it. Serum PTHrP level was not changed in W256/S-bearing rats. Osteoporosis-like changes, bone weight loss, low contents of bone calcium and phosphorus, and a decrease in the bone mineral density (BMD), were observed in the femur 14 days after the tumor inoculation. There was a pronounced decrease in the serum 17β-estradiol level during the tumor growth. The reduction of BMD of femurs in W256/S-bearing rats was significantly inhibited by treatment with salmon calcitonin or 17β-estradiol. On the basis of these results, W256/S Carcinoma-bearing rats seem to be a useful model for osteoporosis of hypoovarianism.
Jullienne A - One of the best experts on this subject based on the ideXlab platform.
-
1,25 DIHYDROXYVITAMIN D AND DEXAMETHASONE DECREASE IN VIVO Walker Carcinoma GROWTH, BUT NOT PARATHYROID HORMONE RELATED PROTEIN SECRETION
Hormone and Metabolic Research, 1995Co-Authors: Martine Cohen-solal, Bouizar Z, M.a. Denne, A. M. Graulet, Gueris J, Bracq S, Jullienne AAbstract:Parathyroid hormone related protein (PTHrP) is produced by several breast cancers. 1,25 dihydroxyvitamin D (1,25[OH]2D) and Dexamethasone (DEX) have been shown to decrease PTHrP mRNA expression in several cell lines. We therefore tested the in vivo effect of both steroids on PTHrP secretion and tumor development of the Walker Carcinoma (WC). WC cells were injected subcutaneously in Fisher rats which were simultaneously treated with either vehicle, or 1,25(OH)2D (0.5 micrograms/kg/d) or DEX (2 mg/kg/d). After 7 days, tumor weight was significantly decreased in the 2 treated-groups as compared to the control group. Vehicle treated-rats developed hypercalcemia, which was also observed in rats treated with 1,25(OH)2D; by contrast, the plasma calcium was significantly decreased in the DEX-treated group compared to vehicle-treated rats. In a dose-effect experiment, this dose of 1,25(OH)2D induced marked hypercalcemia in rats not implanted with WC, but was required to decrease the tumor weight in implanted rats. In both 1,25(OH)2D and DEX-treated groups, plasma PTHrP levels were significantly decreased, but there was a similar correlation between PTHrP plasma level and tumor weight in the three groups. Indeed, the cytosolic PTHrP content/mg tumor was identical in the 3 groups. By contrast, the PTHrP/Actin mRNA in the tumor was significantly decreased in the 1,25(OH)2D group, comparatively to the vehicle and DEX groups. Our results show that Dexamethasone and 1,25(OH)2D decrease WC tumor development in vivo, but do not change the PTHrP secretion by the remaining tumor although steady state PTHrP mRNA content level is decreased by 1,25(OH)2D.
Kenichi Miyamoto - One of the best experts on this subject based on the ideXlab platform.
-
Osteoporosis-like changes in Walker Carcinoma 256-bearing rats, not accompanied with hypercalcemia or parathyroid hormone-related protein production.
Japanese Journal of Cancer Research, 1995Co-Authors: Yoshihiro Waki, Kenichi Miyamoto, Shohei Kasugai, Keiichi OhyaAbstract:Walker Carcinoma 256 (W256) was reported to induce hypercalcemia dependent on bone metastasis and/or parathyroid hormone-related protein (PTHrP) in the rat, providing a model of the humoral hypercalcemia of malignancy. In this study, after the subcutaneous inoculation of cells of the W256/S line, which is maintained in this laboratory, into young female Wistar Imamichi rats (6 weeks old), serum calcium and phosphorus levels changed only within the control range, whereas serum alkaline phosphatase activity and urinary calcium level significantly increased and urinary phosphorus decreased during the tumor growth, resulting in hypercalciuria and hypophosphaturia. W256/S did not express PTHrP-mRNA, whereas LLC-W256 cells did express it. Serum PTHrP level was not changed in W256/S-bearing rats. Osteoporosis-like changes, bone weight loss, low contents of bone calcium and phosphorus, and a decrease in the bone mineral density (BMD), were observed in the femur 14 days after the tumor inoculation. There was a pronounced decrease in the serum 17β-estradiol level during the tumor growth. The reduction of BMD of femurs in W256/S-bearing rats was significantly inhibited by treatment with salmon calcitonin or 17β-estradiol. On the basis of these results, W256/S Carcinoma-bearing rats seem to be a useful model for osteoporosis of hypoovarianism.