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H Isono

Publications and source records attributed to H Isono.

At least 55 records · Page 3Linked to original sources
PubMed1992

Effects of short-term treatment with calcium on the parathyroid glands in golden hamsters of different ages, with special reference to large vacuolar bodies.

The effects of different ages on large vacuolar bodies in the parathyroid glands of golden hamsters after short-term treatment with calcium were investigated. In the parathyroid glands of the young and adult animals 15 min and the senile animals 15 and 60 min after administration of calcium, the percent area occupied by large vacuolar bodies was significantly increased as 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 acute hypercalcemia. 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.

Aging↗
PubMed1992

Stereological studies of the parathyroid gland of phosphate-treated golden hamsters subjected to a hypergravity environment.

The ultrastructure of the parathyroid glands of phosphate-treated golden hamsters exposed to a 5-G environment was studied. In the phosphate-treated animals exposed to a hypergravity environment, the Golgi complexes associated with numerous prosecretory granules, and the enlarged intercellular spaces containing floccular or finely particulate material showed a significant increase compared to those of the control, centrifuged, and phosphate-treated groups, and the cisternae of the granular endoplasmic reticulum showed a significant increase compared to those of the control and phosphate-treated groups. In addition, numerous secretory granules were situated close to the plasma membrane of chief cells in the phosphate-treated animals exposed to a hypergravity environment. These findings suggest that the synthesis, and to a greater extent the release of secretory granules may be markedly stimulated, in the parathyroid glands of phosphate-treated animals exposed to a hypergravity environment.

Animals↗
PubMed1992

Ultrastructure of the parathyroid gland of fetal and pregnant golden hamsters subjected to hypergravity environment.

The ultrastructure of the parathyroid glands of fetal and pregnant golden hamsters exposed to 5-gravity environment was studied. In the centrifuged fetal animals the Golgi complexes associated with some prosecretory granules were significantly increased compared with those of the control fetal animals, and several secretory granules were located in a peripheral position just beneath the plasma membrane. In the centrifuged pregnant animals the Golgi complexes associated with numerous prosecretory granules were significantly increased, cisternae of the granular endoplasmic reticulum appeared to be increased compared with those of the control pregnant animals, many secretory granules were located in the peripheral cytoplasm and several granules were situated close to the plasma membrane. These findings suggest that in the parathyroid glands of the fetal golden hamsters as well as the pregnant animals the synthesis and release of parathyroid hormone may be stimulated in response to a hypergravity environment.

Animals↗
PubMed1992

Effects of hypergravity environment on the parathyroid gland of the norepinephrine-treated golden hamster: a stereological study.

Effects of 5-gravity environment on the ultrastructure of the parathyroid glands of norepinephrine-treated golden hamsters were studied. In the centrifuged animals treated with norepinephrine, the volume density occupied by the Golgi complexes associated with numerous prosecretory granules was significantly increased compared with that of the control, centrifuged and norepinephrine-treated animals, as well as the volume density occupied by the cisternae of the granular endoplasmic reticulum compared with that of the control and centrifuged animals. In addition, in the centrifuged animals treated with norepinephrine, numerous secretory granules were situated close to the plasma membrane. It is suggested that the synthesis and release of secretory granules may be markedly stimulated in the parathyroid glands of the norepinephrine-treated golden hamsters subjected to a hypergravity environment.

Adrenergic alpha-Agonists↗
PubMed1992

Ultrastructure of the water-clear cell in the rabbit parathyroid gland.

The ultrastructure of water-clear cells has been described in human hyperplastic parathyroid glands. However, previous studies have failed to demonstrate this type of cell in normal human or other vertebrate parathyroid glands. Upon recently recognizing water-clear cells in the parathyroid glands of the golden hamster, we intended to examine the occurrence of these cells in other animals. In the present study the parathyroid glands of about one-year-old rabbits were observed by electron microscopy. Water-clear cells containing numerous vacuoles were demonstrated dispersed among the chief cells. The cells were generally situated close to the basal lamina of perivascular space which lay against the capillary vessel and were attached by desmosomes to the chief cells. Irregularly shaped vacuoles in the water-clear cells resembled dilated cisternae of the granular endoplasmic reticulum in the chief cells. Several ribosomes could be seen attached to the membrane of some of the irregularly shaped vacuoles. It is conceivable that the water-clear cells are transformed from the chief cells.

Animals↗
PubMed1992

Effects of starvation on the water-clear cell in the golden hamster parathyroid gland.

Changes of the water-clear cells of the parathyroid glands in adult and senile golden hamsters 2 and 5 days after starvation were investigated. The ultrastructure of the water-clear cells of the parathyroid glands in the starved adult and senile animals almost resembled that of the control adult and senile animals. However, lipid droplets were very numerous in the water-clear cells in the adult and senile animals after starvation. It is considered that starvation affects functional activity in the water-clear cells of the parathyroid gland.

Age Factors↗
PubMed1992

[Changes in retinal blood flow volume in experimental retinal vein compression].

The authors quantitated the retinal blood flow volume during and immediately after experimental compression of the temporal retinal vein in 5 Macaca fuscata monkey eyes. The hydrogen clearance method was used to quantitate the retinal blood flow volume. After placing a microelectrode on the retinal surface, we measured the blood flow volume 4 times at a 15-minute interval. This value served as a baseline for the experiments. Next we compressed the temporal retinal vein near the disc with a 25-gauge needle with a rounded tip under guidance by an indirect ophthalmoscope. We measured the blood flow volume during compression. The compression was maintained for 3 minutes. Further blood flow determination was performed 7 minutes after release of compression and was repeated 4 times at a 15-minute interval. During compression of the temporal retinal vein, the retinal blood flow volume in the area served by the vein decreased by an average of 35%. The flow volume recovered rapidly and remained stable after release of compression. There was no reactive hyperemia. This model appears useful to elucidate the retinal circulation of branch retinal vein occlusion.

Animals↗
PubMed1992

An in vitro study on the effects of melatonin on the ultrastructure of the hamster parathyroid gland.

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.

Animals↗
PubMed1992

[Spectral absorption characteristics of ocular tissues].

We studied the ocular spectral characteristics of monkey and rabbit eyes in the range of 300 to 900 nm. Measurements were performed on dissected specimens of the cornea, lens, vitreous, sensory retina and retinal pigment epithelium (RPE) plus choroid. Xanthophyll and monkey blood were also studied. Components of the ocular media showed high absorption over the ultraviolet range. The absorption curve of the sensory retina was similar to that of the ocular media. RPE plus choroid showed high absorption over the whole spectral range, with gradual decrease in absorption above 600 nm. The specific absorption curve of both xanthophyll and blood became manifest only when diluted to more than 1:20,000 in the former and to more than 1:100 in the latter. The spectral absorption of the ocular tissue thus became specific only when the thickness or density of the tissue was within a certain range.

Animals↗
PubMed1992

[Blood flow in the optic nervehead following intravenous administration of calcium antagonist].

The authors quantitated the blood flow of the optic nervehead after intravenous administration of calcium antagonist. The hydrogen clearance method was used to measure the blood flow after placing an electrode sensor in the optic nervehead of 9 eyes of 5 Macaca fuscata monkeys, under general anesthesia by intravenous pentobarbital sodium. 5 micrograms/kg of nicardipine, a calcium antagonist, was rapidly injected into the femoral vein. Measurement of blood flow in the optic nervehead was started 5 minutes after injection until 90 minutes at intervals of 15 minutes. A dose of 2 micrograms/kg/min nicardipine was then administered intravenously for another 90 minutes. During the experiment, intraocular pressure was maintained at 15 mmHg under continuous monitoring of systemic blood pressure. The blood flow in the optic nervehead decreased to 83% 5 minutes after injection. It increased slowly and reached the initial value 50 minutes later. It reached 108% of the initial value 80 minutes after injection. During the additional infusion of nicardipine, the blood flow decreased slowly and reached 85% of the initial value. It is concluded that the blood flow in the optic nervehead changed depending on the method, quantity and duration after injection of intravenous calcium antagonist. The blood flow decreased immediately after administration. The main cause of this phenomenon was thought to be due to decrease of perfusion pressure secondary to decrease of systemic blood pressure.

Animals↗
PubMed1991

Hybrid formation of rabbit and rat hepatic glutathione S-transferases.

1. A reconstitution experiment resulted in the formation of new proteins between limited combinations of rat and rabbit hepatic glutathione S-transferases: AA(subunit composition: YcYc) and R3b(Y3Y3), Lig(YaYa) and R3b(Y3Y3), and A(Yb1Yb1) and R2(Y2Y2). 2. It was demonstrated that the new protein formed between R2 and A had the subunit composition of Y2Yb1, suggesting a hybrid of rabbit (R2) and rat isozyme (A). 3. This hybrid protein showed intermediate spec. acts between those of R2 and A when either 1-chloro-2,4-dinitrobenzene (CDNB) or 1,2-dichloro-4-nitrobenzene (DCNB) was employed as the substrate.

Animals↗
PubMed1991

Ultrastructural studies on the effects of hypergravity environment on the parathyroid glands in golden hamsters of different ages.

The ultrastructure of the parathyroid glands of infantile, young, adult and senile golden hamsters subjected to a hypergravity environment was studied. In the parathyroid glands of 5-, 10- and 20-day-old, and 1- and 3-month-old golden hamsters exposed to a hypergravity environment, the Golgi complexes were significantly increased, and in 5-, 10- and 20-day-old, and 1- and 8-month-old animals exposed to a hypergravity environment, the cisternae of the granular endoplasmic reticulum appeared to be increased as compared to those of each control group. In addition, in centrifuged animals numerous prosecretory granules were observed in the Golgi areas, and many secretory granules were located in the peripheral cytoplasm. The ultrastructure of the parathyroid glands of 14-month-old centrifuged animals resembled that of 14-month-old control animals. These results suggest that the secretory activity of the parathyroid gland may be stimulated in infantile, young and adult golden hamsters subjected to a hypergravity environment and may not be stimulated in senile animals subjected to a hypergravity environment.

Aging↗
PubMed1991

Electron-microscopic study of the parathyroid gland of epinephrine-treated golden hamsters subjected to hypergravity environment.

The ultrastructure of the parathyroid glands of golden hamsters subjected to 5-gravity environment after administration of epinephrine was studied. In the epinephrine-treated animals exposed to a hypergravity environment, the Golgi complexes associated with numerous prosecretory granules were significantly increased compared with those of the control, centrifuged and epinephrine-treated animals, as well as the cisternae of the granular endoplasmic reticulum compared with those of the control and centrifuged animals. In addition, many secretory granules were situated close to the the plasma membrane of the chief cells in the epinephrine-treated animals exposed to a hypergravity environment. Those observations suggest that the secretory activity of the parathyroid gland may be markedly stimulated in the epinephrine-treated animals exposed to a hypergravity environment.

Animals↗
PubMed1991

[Anatomical study on the branches of the celiac trunk (IV). Comparison of the findings with Adachi's classification].

The authors studied the mode of branching of the celiac trunk in 184 Japanese cadavers during dissecting practice at Gifu University from 1985 to 1988. The findings were as follows; 1) One hundred and sixty-six of the 184 cases belonged to Type I of Adachi's classification of variation in the arrangement of the branches of the celiac trunk. One hundred and twenty-nine cases belonged to Group 1, one case to Group 2, 10 cases to Group 3, 9 cases to Group 4, one case to Group 6, 2 cases to Group 7, 8 cases to Group 8 and 4 cases to Group 11. Two cases did not belong to any group. One of them had an anastomosis between the hepatic artery and the superior mesenteric artery. The other one had the middle colic artery arising from the hepatic artery. 2) Seven cases belonged to Type II, Group 12. 3) Two cases belonged to Type III. One belonged to Group 18. The other one had an accessory right hepatic artery arising from the superior mesenteric artery. 4) One case belonged to Type IV, Group 20. 5) Three cases belonged to Type V, Group 23. 6) Two cases belonged to Type VI. One case had a gastrolienal trunk and an accessory right hepatic artery arising from the superior mesenteric artery. The other one had a gastrolienal trunk and an accessory right hepatic artery arising from the gastrolienal trunk. 7) Of the 184 cases, three could not be classified according to Adachi. Two cases had a gastrolienal trunk and the hepatic artery arising from the abdominal aorta. One case had a lienomesenteric trunk and a gastrohepatic trunk.

Aged↗
PubMed1991

Ultrastructural study on the effects of hypophysectomy on the golden hamster parathyroid gland.

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.

Animals↗
PubMed1991

Effects of melatonin on the ultrastructure of the golden hamster parathyroid gland.

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 poorly-developed 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.

Animals↗
PubMed1991

Ultrastructure of mass of floccular substance in the parathyroid gland of golden hamster.

Mass of floccular substance was observed in the parathyroid glands of fetal, newborn and infantile 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 cell organelles were detected within area of mass.

Animals↗