Ultrastructural Change in the Parathyroid Gland of the Phosphate Treated Newt, <i>Triturus pyrrhogaster</i> (Boié)

Abstract

Summary. The newt parathyroid gland in natural hibernation and in hyperfunctional conditions induced by the intraperitoneal injection of phosphate was electron-microscopically studied. The average numbers of mitochondria, Golgi apparatus, large homogeneously dense bodies, large heterogeneously dense bodies, vacuolar bodies and lipofuscin-like thyroid glands of the phosphate treated and hibernating (control) newts. The parenchymal cells of the newt parathyroid gland were classified into basal cells and suprabasal cells. Daily administration of phosphate caused no marked changes in the former cells. In the latter under experimental conditions, granular and agranular endoplasmic reticula and small dense granules seemed to be increased in number, while glycogen granules appeared decreased in number when contrasted to those in the control newts. The Golgi apparatus and large homogeneously dense bodies were increased in number reaching a maximum after 7 days of phosphate administration, and lipofuscin-like bodies were gradually increased in number during the experimental stages. On the contrary, vacuolar bodies were first rapidly, then gradually decreased in number. Large heterogeneously dense bodies subdivided into a vesicular type and lysosomal type were slightly decreased during 14 days' administration of phosphate and increased in number after 21 day administration. Under experimental conditions the vesicular type heterogeneously dense bodies were more dominant than the lysosomal type. The numbers of mitochondria were hardly varied as compared with control newts. The ultrastructure of the normal parathyroid gland has been studied extensively. Furthermore, a number of investigations on the fine structure of the parathyroid gland under experimentally hyper-or hypo-functional conditions have been reported in the rat (DAVIS and ENDERS, 1961;RAISZ, 1964, 1966;LEVER, 1965;MAZZOCCHI et al., 1967;HARA and NAGATSU, 1968;ROTH et al., 1968; ROHR and KRASSIG, 1968), frog (MONTSKO et al., 1963a;LANGE and BREHM, 1965), cow (CAPEN et al., 1965), rabbit (MELSON, 1966; TANAKA, 1969a, b; TANAKA et al., 1969a, b), mouse (STOECKEL and PORTS, 1966b;NAKAGAMI, 1967), cat (CAPEN and ROWLAND, 1968) and bat (AZZALI, 1970).However, the morphology of the secretory cycle of the parathyroid gland is still a matter of speculation.By comparison of the parathyroid gland of the naturally hibernating newt (SETOGUTI, ISONO and SAKURAI, 1970a) with phosphate treated ones the present paper aims at the elucidation of the correlations of different types of inclusion bodies in the gland: small dense granules, large homogeneously dense bodies, large heterogeneously dense bodies, vacuolar bodies containing uncoated vesicles and/or coated ones, and Materials and MethodsThe experimental animals used for this work were adult newt, Triturus pyrrhowere daily given 0.4ml of 1% Na2HPO4 solution (phosphate) intraperitoneally for 3, 7, 14 and 21 days.The parathyroid glands from naturally hibernating (control) newts and those treated with phosphate were removed ...

Effects of cadmium on the ultrastructure of the mouse parathyroid gland

“…These changes in the experimental mice are thought to be in duced by stimulating the secretory process in most chief cells. These results are fairly con sistent with the observations which demon strate the increase in functional activity of the parathyroid gland [Melson, 1966;Capen and Rowland, 1968;Fetter and Capen, 1970;Yousliak and Capen, 1970;Furuta, 1971;Isono et al, 1971;Altendhr, 1972;Fujii and Isono, 1972;Isono and Shoumura, 1973;Anderson and Capen, 1976 ;Chan, 1977;Isono eta!., I976a,b;Takai, 1976;Coleman and Silbermann, 1978].…”

Stereological Studies of the Parathyroid Gland of Phosphate-Treated Golden Hamsters Subjected to a Hypergravity Environment

“…Furthermore, in the parathyroid gland of the rat within 3 h of phosphate treatment, the surface area of the Golgi com plex and secretory granules is decreased, but after 3 h their surface area is increased, and after 12 h the surface area of the cisternae of the granular endoplasmic reticulum is also increased [4], In the present study, in the parathyroid glands of the P group, cisternae of the granular endoplas mic reticulum were significantly increased and the Golgi complexes appeared to be increased as compared to those of the control group. These results are essentially similar to previous observations showing an increase in function of the parathyroid glands of phosphate-treated animals [1][2][3], Therefore, it is suggested that the synthesis and release of secretory granules may be markedly stimulated in the para thyroid glands of the P-5G group.…”

Amphibian parathyroids: Morphological and functional aspects

“…These cells have been suggested to play a role as supporting cells (Isono et al, 1971(Isono et al, , 1990Setoguti et al, 1970a).…”

“…Parathyroid hormone-induced hypercalcemia in Triturus pyrrhogaster led to a hypofunctional state of suprabasal cells as exhibited by transformed secretory granules into vacuolar bodies through lysosomal type heterogenously dense bodies or some of them through the vesicular type (Isono and Shoumura-Sakurai, 1973). Hyperfunctional conditions have been induced in the parathyroid glands of Triturus pyrrhogaster after injection of phosphate (Isono et al, 1971) or EDTA , resulting in an increase of RER, Golgi complex, large homogenous dense bodies, and lipofuscin-like bodies and a decrease in the number of glycogen granules and vacuolar bodies in the suprabasal cells. The number of mitochondria1 profiles hardly varied as compared to controls.…”