DigitalUM :: Browsing by Subject "Parathyroid gland"

Browsing by Subject "Parathyroid gland"

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Open Access
Age-related changes of the ultrastructure in the cardiomyopathic hamster (UM-X7.1 Syrian hamster) parathyroid gland
(Murcia : F. Hernández, 2004) Utsumi, M.; Moriguchi, K.; Takahashi, H.; Kinoshita, C.; Togari, A.; Mizutani, M.; Ohno, N.
We qualitatively and quantitatively investigated parathyroid glands of the UM-X7.1 cardiomyopathic hamster at 1, 2, 6 and 12 months of age to compare them with those of the normal hamster. We found that at 1 month of age in the UM-X7.1 hamster, the Golgi apparatus, lipid droplets and secretory granules decreased. There were no significant differences between the UM-X7.1 hamster and the control hamster at 2 months of age. At 6 months of age, the Golgi apparatus, rER and the secretory granules significantly increased in the UM-X7.1 hamster. At 12 months of age, the Golgi apparatus and lysosomes increased, while the secretory granules decreased. Ultrastructurally, we consider that in the UM-X7.1 hamster, the synthesis and release of the parathyroid at 6 months of age may be activated by an excessive amount of circulating catecholamine, and the functional activity of the parathyroid glands at 12 months of age may be depressed by the increased plasma calcium level. These findings suggest that the activities of the synthesis and release of the parathyroid hormone were the highest at 6 months of age in the UM-X7.1 hamster.
Open Access
An in vitro study on the effects of melatonin on the ultrastructure of the hamster parathyroid gland
(Murcia : F. Hernández, 1992) shoumura, S.; chen, H.; Emura, S.; Utsumi, M.; Hayakawa, D.; Yamahira, T.; Terasawa, K.; Tamada, A.; Arakawa, M.; Isono, H.
Isolated parathyroid glands from adult female golden hamsters were incubated on a black Millipore filter in an incubation vessel containing Ham's F-12 medium, with or without melatonin at final concentration of 10-5 M for 1 hour. In the parathyroid glands used for in vitro treatments with melatonin, the Golgi complexes associated with a few prosecretory granules and cisternae of the rough endoplasmic reticulum showed a significant decrease, and lipid droplets and lysosomes appeared to be increased compared with those of the control parathyroid glands. These changes are considered to be induced by suppression of the synthesis of parathyroid hormone in parathyroid glands incubated in a vessel containing medium with melatonin.
Open Access
Effects of cigarette smoke exposure on the utlrastructure of the golden hamster parathyroid gland
(Murcia : F. Hernández, 2002) Yano, R.; Hayakawa, D.; Emura, S.; chen, H.; Ozawa, Y.; Taguchi, H.; Shoumura, S.
Cigarette smoking has been identified as one of the risk factors to induce osteoporosis. However, we find no study on the morphology of the parathy r o i d gland under smoking exposure. We studied the ultrastructure of the parathyroid gland, lung and femur of the golden hamster exposed to cigarette smoke. Fourweek- old male hamsters were housed in a plastic case (48x31x30 cm) and were exposed to cigarette smoke for 12 weeks, 5 minutes exposure, 4 times a day, 4 days a week. There were no differences in serum calcium level and the whole bone mineral density between the control and the smoke-exposed groups. In the parathyroid gland of the smoke - exposed animals, the Golgi complexe s associated with many prosecretory granules were well d eveloped and many secretory granules were located near the plasma membrane. Large lipid-like inclusion bodies were observed in the alveolar macrophages of the smoke-exposed animals. The femur morphology showed a wider area of resorbing surface in the smoke-exposed group than in the control group. From these findings, it is conceivable that the secretory activity of the p a r a t hyroid gland was stimulated with cigarette smoke exposure.
Open Access
Effects of isoproterenol on the fine structure of the hamster parathyroid gland
(Murcia : F. Hernández, 1988) Shizuko Shoumura; Yuji Iwasaki; Noriko Ishizaki; Shoichi Emura; Tomo Yamahira; Masaki Ito; Hideo Isono
Ultrastructural changes of the parathyroid glands of isoproterenol-treated golden hamsters were investigated. Many chief cells in the parathyroid glands after 5 and 10 minutes of administration of isoproterenol contain well-developed Golgi complexes and granular endoplasmic reticulum, numerous prosecretory granules, and many secretory granules in the peripheral cytoplasm as compared with the control animals. Many chief cells in the parathyroid glands after 1,3,6 and 12 hours of administration have poorly-developed Golgi complexes, granular endoplasmic reticulum, many secretory granules and numerous lipid droplets as compared with the control animals. The morphology of the parathyroid gland after 30 minutes and 24 hours of administration resembles that of the control animals. It is considered that isoproterenol affects the secretory activity of the parathyroid gland.
Open Access
Effects of long-term treatment with ethanol on the ultrastructure of the golden hamster parathyroid gland
(Murcia : F. Hernández, 1999) chen, H.; Hayakawa, D.; Emura, S.; Tamada, A.; Jamali, M.; Ozawa, Y.; Taguchi, H.; Yano, R.; Ohtake, N.; Shoumura, S.
The ultrastructure of the parathyroid gland in golden hamsters after long-term treatment with ethanol was studied. Male hamsters of experimental groups were given ethanol at the concentration of 7% for 3 and 5 months with food and water freely available. In the ethanol-treated hamsters, the Golgi complexes associated with many prosecretory granules were well developed and many secretory granules were located near the plasma membrane as compared with those of the control animals. Exocytotic events were observed in 5-month-treated animals. These findings suggest that the secretory activity of the parathyroid gland is stimulated after long-term treatment with ethanol.
Open Access
Effects of melatonin on the ultrastructure of the golden hamster parathyroid gland
(Murcia : F. Hernández, 1991) Huayue Chen; Shizuko Shoumura; Shoichi Emura; Michiya Utsumi; Tomo Yamahira; Hideo Isono
Ultrastructural changes of the parathyroid glands of melatonin-treated golden hamsters were studied. Many chief cells in the parathyroid glands after 1 hour of administration of melatonin contained poorlydeveloped Golgi complexes associated with a few prosecretory granules and numerous lipid droplets as compared with those of the control animals. The morphology of the parathyroid glands after 5 hours of administration resembled that of the control animals. Many chief cells in the parathyroid glands after 24 hours of administration had well-developed Golgi complexes and cisternae of the granular endoplasmic reticulum, numerous prosecretory granules, a few lipid droplets and many secretory granules in the peripheral cytoplasm as compared with those of the control animals. The ultrastructure of the parathyroid glands after 48 hours of administration was almost similar to that of the control animals. It is considered that melatonin affects the secretory activity of the parathyroid gland.
Open Access
Effects of pinealectomy on the ultrastructure of the golden hamster parathyroid gland
(Murcia : F. Hernández, 1990) Huayue Chen; Shizuko Shoumura; Shoichi Emura; Michiya Utsumi; Tomo Yamahira; Hideo Isono
Ultrastructural changes of the parathyroid glands of pinealectomized golden hamsters were investigated. The main changes in the parathyroid glands 1 hour and 1 day after pinealectomy compared with the control and sham-operated groups were an increase of the Golgi complexes, cisternae of the granular endoplasmic reticulum and large vacuolar bodies. In addition, many chief cells contained numerous prosecretory granules in the Golgi areas and many secretory granules in the peripheral cytoplasm. The morphology of the parathyroid glands 7 and 30 days after pinealectomy resembled that of the control parathyroid glands. These results suggest that pinealectomy affects the secretory activity of the parathyroid gland.
Open Access
Effects of progesterone on the ultrastructure of the golden hamster parathyroid gland
(Murcia : F. Hernández, 1995) Emura, S.; Hayakawa, D.; Yamahira, T.; Terasawa, K.; Tamada, A.; Arakawa, M.; Isono, H.; Shoumura, S.
The ultrastructure of the parathyroid glands in golden hamsters after administration of progesterone was investigated. In the parathyroid glands of the female hamsters after administration of progesterone, the mean serum calcium concentration was significantly higher when compared to that of the control hamsters. In the male experimental hamsters, the percentage area occupied by Golgi complexes and lipid droplets was significantly increased when compared to that of the control hamsters, respectively. In the female hamsters after administration of progesterone, the percentage area occupied by large vacuolar bodies was significantly decreased when compared to that of the control hamsters. In the male and female experimental hamsters, the mean number of secretory granules per 100 pm2 of cytoplasm showed a significant increase compared with that of the male and female control hamsters, respectively. These findings suggest that the secretory activity of the parathyroid glands may be stimulated in response to hypocalcemia induced by progesterone.
Open Access
Effects of prostaglandin Eq on the ultrastructure of the golden hamster parathyroid gland
(Murcia : F. Hernández, 1994) Emura, S.; Utsumi, M.; Hayakawa, D.; Yamahira, T.; Terasawa, K.; Tamada, A.; Isono, H.; Shoumura, S.
The effects of different ages on large vacuolar bodies in the parathyroid glands of golden hamsters after administration of prostaglandin E2 (PGE2) were investigated. In the parathyroid glands of the young and senile animals 15 min and the senile animals 60 min after administration of PGE2, the mean serum calcium concentration was significantly higher when compared to that of the young and senile control animals, respectively. In the experimental adult animals 60 min after administration of PGE2, the serum calcium concentration was seen to increase. In the parathyroid glands of the young animals 15 min and the adult and senile animals 60 min after administration of PGE2, the percent area occupied by large vacuolar bodies was significantly increased when compared to that of the young, adult and senile control animals, respectively. These findings suggest that the percent area occupied by large vacuolar bodies is increased in response to hypercalcemia induced by PGE2. It is thought that in the parathyroid glands suppressed by hypercalcemia there is a relationship between the percent area occupied by large vacuolar bodies and aging.
Open Access
Effects of short-term treatment with CaCI2 or EDTA on the parathyroid glands in pregnant golden hamsters, with special reference to large vacuolar bodies
(Murcia : F. Hernández, 1997) Emura, S.; Hayakawa, D.; chen, H.; Terasawa, K.; Tamada, A.; Isono, H.; Shoumura, S.
The large vacuolar bodies in the parathyroid glands of pregnant golden hamsters after administration of CaC12 or EDTA were investigated. In the parathyroid glands of the pregnant animals 15 min after administration of CaC12, the mean serum calcium concentration was significantly high when compared to that of the control animals. In the parathyroid glands of the pregnant animals 15, 30 and 60 min after administration of EDTA, the mean serum calcium concentration was significantly low when compared to that of the control animais. In the parathyroid glands of the pregnant animals 15 min after administration of CaC12, the percentage area occupied by large vacuolar bodies was significantly increased when compared to that of the control animals. In the parathyroid glands of the pregnant animals 15 min after administration of EDTA, the percentage area occupied by large vacuolar bodies was significantly decreased when compared to that of the control animals.
Open Access
lmmunocytochemical localization of parathyroid hormone in rabbit parathyroid glands
(Murcia : F. Hernández, 1988) Shizuko Shoumura; Noriko Ishizaki; Shoichi Emura; Yuji Iwasaki; Tomo Yamahira; Hideo Isono
Immunocytochemical localization of parathyroid hormone was examined in the rabbit parathyroid gland by means of protein A-gold technique. Protein A-gold particles were observed on the secretory granules and the large secretory granules thought to be storage granules. No protein A-gold particles were observed on cisternae of the endoplasmic reticulum and the Golgi apparatus
Open Access
Morphological identification of the lipid-storing cells in golden hamster parathyroid glands after vitamin A treatment
(Murcia : F. Hernández, 2001) chen, H.; Hayakawa, D.; Emura, S.; Ozawa, Y.; Taguchi, H.; Yano, R.; Shoumura, S.
We investigated hamster parathyroid glands of different ages using electron microscopy and found a new cell type in young, adult and senile hamsters. Theses special cells were located in interstitial tissues and invariably contained severa1 lipid droplets within the cytoplasm. The cells showed an elongated spindle with some cell processes. The cells contained small Golgi complexes and moderate cisternae of the granular endoplasmic reticulum. The morphological characteristics of these cells were mostly the same as those of lipid-storing cells in other organs (Yamada and Hirosawa, 1976). After vitamin A administration, the lipid droplets in these cells markedly increased in number and also in volume density. The other morphological features of these cells resembled those of the control animals. We called these cells parathyroid lipid-storing cells. They may incorporate and store vitamin A within the lipid droplets. They can be classified as one of the cellular components in hamster parathyroid gland.
Open Access
Ultrastructural study on the effects of hypophysectomy on the golden hamster parathyroid gland
(Murcia : F. Hernández, 1991) Shoichi Emura; Shizuko Shoumura; Michiya Utsumi; Huayue Chen; Tomo Yamahira; Daisuke Ayakawa; Michio Arakawa; Hideo Isono
The ultrastructure of the parathyroid glands of hypophysectomized golden hamsters was studied. In the parathyroid glands of hypophysectomized animals the Golgi complexes and secretory granules were significantly decreased and large vacuolar bodies were significantly increased compared with those of the control animals. In addition. the chief cells contained a few prosecretory granules in the Golgi areas and a few secretory granules were present in the peripheral cytoplasm. These results suggest that the synthesis and release of parathyroid hormone may be suppressed in the parathyroid glands of the hypophysectomized animals.
Open Access
Ultrastructure of mass of floccular substance in the parathyroid gland of golden hamster
(Murcia : F. Hernández, 1991) Shoichi Emura; Shizuko Shoumura; Michiya Utsumi; Huayue Chen; Tomo Yamahira; Daisuke Ayakawa; Michio Arakawa; Hideo Isono
Mass of floccular substance was observcd in the parathyroid glands of fetal, newborn and infantilc golden hamsters. Mass composed of floccular substances was spherical with no limiting membrane around it. It was located near the nucleus and the Golgi area, but was also observed in the peripheral cytoplasm. No ccll organelles were detected within area of mass.
Open Access
Ultrastructure of the parathyroid gland
(Murcia : F. Hernández, 1990) Hideo Isono; Shizuko Shoumura; Shoichi Emura
Open Access
Ultrastructure of the parathyroid gland of the young golden hamster after short-term treatment with ethanol
(Murcia : F. Hernández, 1998) chen, H.; Hayakawa, D.; Emura, S.; Tamada, A.; Jamali, M.; Yamahira, T.; Yoshida-Terasawa, K.; Isono, H.; Shoumura, S.
We studied the ultrastructure of the parathyroid gland of young golden hamsters after short-term treatment with ethanol (1.5 gkg bw or 6.0 gkg bw). We did not find any ultrastructural changes of the parathyroid gland after administration of 1.5 g/kg ethanol. In the hamsters, 3 hours after administration of 6.0 g!kg ethanol, the mean serum calcium concentration was significantly low as compared to that of the control animals. In the parathyroid gland 1 hour after administration of 6.0 glkg ethanol, the Golgi complexes associated with a few prosecretory granules and the volume density occupied by the Golgi complexes decreased compared with that of the control animals. In the parathyroid glands 3 hours after administration of 6.0 g/kg ethanol, the Golgi complexes decreased as compared with those of the control animals, while the large vacuolar bodies increased. These findings suggest that the cellular activity of the parathyroid gland is suppressed after short-term treatment with ethanol. Intracellular lumen was found in the parathyroid chief cells 3 hours after administration of 6.0 &kg ethanol, and the significance of this structure is discussed.

Browsing by Subject "Parathyroid gland"

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