Summary
The structure of the PAS-positive calcium-sensitive (Ca-s) cells of the pars intermedia was investigated in eels kept in deionized water (DW) or fresh water (FW) supplemented with Ca2+ or Mg2+. Ca2+ (2mM) reduces considerably the response to DW; plasma osmolarity, Na+ and Ca2+ levels are not significantly affected. In eels adapted to DW for 21 or 28 days, showing highly stimulated Ca-s cells, an addition of CaCl2 for 2 days inhibits the release of granules, but does not immediately block their synthesis and the mitotic activity. The nuclear area is reduced, osmolarity and plasma sodium increase, but the rise in calcium is not always significant. Magnesium, at a 10-fold greater concentration than in FW (2 mM), slightly inhibits the release of secretory granules without reducing other indicators of stimulation. In Ca-enriched FW, the Ca-s cells appear inactive. These data show that the PAS-positive cells in the pars intermedia of the eel are calcium-sensitive, similar to those of the goldfish; their role in calcium regulation is briefly discussed.
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References
Bower A, Hadley ME (1972) Ionic requirements for melanophore-stimulating hormone (MSH) release. Gen Comp Endocrinol 19:147–158
Chan DKO, Chester Jones I (1968) Regulation and distribution of plasma calcium and inorganic phosphate in the European eel (Anguilla anguilla L.). J Endocrinol 42:109–117
Cuthbert AW, Maetz J (1972) The effect of calcium and magnesium on sodium fluxes through gills of Carassius auratus L. J Physiol (Lond) 221:633–643
Fleming WR, Stanley JG, Meier AH (1964) Seasonal effects of external calcium, estradiol, and ACTH on the serum calcium and sodium levels of Fundulus kansae. Gen Comp Endocrinol 4:61–67
Lwowski ES (1978) The corpuscles of Stannius and calcified tissues in the eel, Anguilla rostrata (L.). Comp Biochem Physiol 59A:183–187
Montskó T, Tigyi A, Lissák K, Duraczky J (1964) Calcium regulation of Teleostei. Acta Physiol Acad Sci Hung 24:63
Nakamura Y, Yamada J (1980) Effects of dietary calcium levels, Ca/P ratios, and calcium components on the calcium absorption rate in carp. Bull Fac Fish Hokkaido Univ 31:277–282
Oduleye SO (1976) The effects of hypophysectomy, prolactin therapy and environmental calcium on electrolyte balance of the brown trout Salmo trutta L. J Exp Biol 64:221–231
Olivereau M (1966) Influence d'un séjour en eau déminéralisée sur le système hypophyso-surrénalien de l'Anguille. Ann Endocrinol (Paris) 27:665–678
Olivereau M (1967) Réactions observées chez l'Anguille maintenue dans un milieu privé d'électrolytes, en particulier au niveau de système hypothalamo-hypophysaire. Z Zellforsch 80:264–285
Olivereau M, Aimar C, Olivereau JM (1980 a) Response of the teleost pituitary (goldfish, eel) to deionized water. Cell Tissue Res 208:389–404
Olivereau M, Aimar C, Olivereau JM (1980 b) PAS-positive cells of the pars intermedia are calcium sensitive in the goldfish maintained in an hyposmotic milieu. Cell Tissue Res 212:29–38
Olivereau M, Aimar C, Olivereau JM (1981a) Réponse de la pars intermedia de l'hypophyse du Cyprin à l'eau désionisée, tamponnée ou non, et à l'apport de calcium ou de magnesium. J Physiol (Paris) in press
Olivereau M, Chambolle P, Dubourg P (1981 b) Ultrastructural changes in the calcium-sensitive (PASpositive) cells of the pars intermedia of eels kept in deionized water and in normal and concentrated sea water. Cell Tissue Res 219:9–26
Olivereau M, Olivereau JM, Aimar C (1981 c) Specific effect of calcium ions on the calcium-sensitive cells of the pars intermedia in the goldfish. Cell Tissue Res 214:23–31
Pang PKT, Pang RK, Sawyer WH (1973) Effects of environmental calcium and replacement therapy on the killifish, Fundulus heteroclitus, after the surgical removal of the corpuscles of Stannius. Endocrinology 93:705–710
Phillips AM, Podoliak HA, Livingston DL, Dumas RF, Thoesen RW (1960) Calcium metabolism in brook trout. Cortland Hatchery Rep 28:17–36
Umehara S, Oguri M (1978) Effects of environmental calcium content on plasma calcium levels in goldfish. Bull Jap Soc Sci Fish 44:827–833
Wendelaar-Bonga SE (1978) The effects of changes in external sodium, calcium and magnesium concentrations on prolactin cells, skin, and plasma electrolytes of Gasterosteus aculeatus. Gen Comp Endocrinol 34:265–275
Wendelaar-Bonga SE (1980) Effect of synthetic salmon calcitonin and low ambient calcium on plasma calcium, ultimobranchial cells, Stannius bodies, and prolactin cells in the teleost Gasterosteus aculeatus. Gen Comp Endocrinol 40:99–108
Wendelaar-Bonga SW, Van der Meij JCA (1980) The effect of ambient calcium on prolactin cell activity and plasma electrolytes in Sarotherodon mossambicus (Tilapia mossambica). Gen Comp Endocrinol 40:391–401
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Olivereau, M., Olivereau, J. Calcium-sensitive cells of the pars intermedia and osmotic balance in the eel. Cell Tissue Res. 222, 231–241 (1982). https://doi.org/10.1007/BF00213209
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DOI: https://doi.org/10.1007/BF00213209