Abstract
The effects of multiple treatment with estradiol dipropionate (EDP) or calcium glucoheptonate (Ca) or a combination of the two on gonadotrophic cells in the pituitary pars distalis of middle-aged female rats were examined. The animals were treated daily for two weeks with EDP (0.625 mg i.p./kg body weight) or Ca (11.4 mg/kg body weight) or EDP+Ca. Luteinising (LH) and follicle stimulating hormone (FSH)-producing cells were examined by immunohistochemistry using antisera to the specific (beta) β-subunits of LH and FSH and a peroxidase–anti-peroxidase immunohistochemical procedure. Plasma levels of FSH and LH were measured by radio-immune assay. A stereological method for determining morphometric parameters in immunopositive FSH and LH cells was used. The number of gonadotrophs per unit area (mm2), their cellular volume and relative volume densities, as well as plasma levels of FSH and LH, were decreased in all treated females in comparison with the controls. The most significant decrease of these parameters was observed in EDP-treated animals. Such changes were also expressed in Ca-treated animals, but the alterations were less distinct. These results demonstrate that multiple EDP or Ca application to middle-aged female rats is able to inhibit, directly or indirectly, the morphofunctional state of gonadotrophic cells in the pituitary pars distalis.
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Aguilar E, Fernandez Galaz C, Vaticon MD, Fejero A, Oriol A (1983) Oestrogen — bromocriptine interaction in the control of luteinizing hormone and prolactin secretion in the neonatally oestrogenized female rat. J Endocrinol 97: 319-325.
Albright F (1974) The effect of hormones on osteogenesis in man. Recent Prog Horm Res 1: 293-353.
Barraclough CA, Haller EU (1970) Positive and negative feed back effect of estrogen on pituitary LH synthesis and release in normal and androgen-sterilized female rats. Endocrinology 86: 542-551.
Bates MD, Conn PM (1984) Calcium mobilization in the pituitary gonadotrope relative role of intra-and extracellular sources. Endocrinology 115: 1380-1385.
Cannigia A, Gennasi C, Borella G (1970) Interstitial absorption of calcium after treatment with oral estrogen and gestagen in senile osteoporosis. Br Med J 4: 30-32.
Chuknyiska RS, Blackman MR, Roth GS (1987) Ionophore A23187 partially reverses LH secretory defect of pituitary cells from old rats. Am J Physiol 253: 233-237.
Clapper DL, Conn PM (1985) Gonadotropin-releasing hormone stimulation of pituitary gonadotrope cells produces an increase in intracellular calcium. Biol Reprod 32: 269-278.
Conn PM (1984) Molecular mechanism of gonadotropin releasing hormone action. In: Litwark G ed. Biochemical Actions of the Hormones. Vol. 11. New York: Academic Press, pp. 67.
Conn PM, Rogers DC, Sandhy FS (1979) Alterations of intracellular calcium level stimulates gonadotropin release from cultured rat pituitary cells. Endocrinology 105: 1122-1127.
Dalkin AC, Haisenleder DJ, Ortolano GA, Suhr A, Marshall JC (1990) Gonadal regulation of gonadotropin subunit gene expression: evidence for regulation of follicle-stimulating hormone-β messenger ribonucleic acid by nonsteroidal hormones in female rats. Endocrinology 127: 798-806.
Finch CE, Felicio LC, Mobbs CV, Nelson JF (1984) Ovarian and steroidal influences on neuroendocrine aging processes in female rodents. Endocrine Rev 5: 467-497.
Frost HM, Jee WSS (1992) On the rat model of human osteoporosis. Bone Miner 98: 227-236.
Fujita T (1985) Calcium and aging. Calcif Tissue Int 37: 1-2.
Girod C (1983) Immunocytochemistry of the vertebrate adenohypophysis. In: Graumann W, Neumann K eds. Handbucher Histochemie. Vol. 8. Jena: Fischer Verlag.
Goltzman D, Tannenbaum GS (1987) Introduction to hypocalcemia by intracerebroventricular injection of calcitonin: evidence for control of blood calcium by nervous system. Brain Res 461: 1-6.
Heaney RP, Recker RR, Saville PD (1978) Menopausal changes in calcium balance performance. J Lab Clin Med 92: 953-963.
Huang C, Pu H-F, Hwang C-Y, Lin J-Y, Yao HC, Tung Y-F, Wang PS (1990) Age-related differences in the release of luteinizing hormone and gonadotropin-releasing hormone in ovariectomized rats. Neuroendocrionology 52: 127-132.
Kamel F, Krey LC (1983) Gonadal steroid modulation of LH secretion stimulated by LHRH, Ca2+ and cAMP. Mol Cell Endocrinol 32: 285-300.
Krieg RJ, Brito AN, Sayles TE, Matt DW (1995) Luteinizing hormone secretion by dispersed anterior pituitary gland cells from middle-aged rats. Neuroendocrinology 65: 318-325.
La Polt PS, Matt DW, Judd HL, Lu JKH (1986) The relation of ovarian steroid levels in young female rats to subsequent estrous cyclicity and reproductive function during aging. Biol Reprod 36: 1131-1139.
Lin T-CH, Pu H-F, Wang PS (1993) Unimpaired postreceptor regulation of luteinizing hormone secretion by gonadotropin-releasing hormone and estrogen in aged rat anterior pituitary cells. Endocrinology 132: 1189-1194.
Lovren M (1989) Pituitary gonadotrophic cells and plasma concentrations of gonadotropins in rats neonatally treated with estrogen. Iugoslav Phisiol Pharmacol Acta 25: 137-144.
Lovren M, Sekulić M (1994) Immunocytochemical and morphometric changes of gonadotrophs during development of oestrogen-sterilized female rats. Yugoslav Med Biochem 13: 13-18.
Lovren M, Sekulić M, Hristić M, Kalafatić D (1989) Ultrastructure of pituitary cells of rats treated with estrogen in perinatal period. Arch Sci Biol 41: 25-31.
Lu JKH, Anzalone CR, La Plot PS (1994) Relations of neuroendocrine functions to reproductive decline during aging in the female rats. Neurobiol Aging 15: 541-544.
Lu JKH, Gilman DP, Meldrum DR, Judd HL, Sawyer CH (1981) Relationship between circulating estrogen and the central mechanisms by which ovarian steroids stimulate luteinizing hormone secretion in aged and young female rats. Endocrinology 108: 836-841.
Matt DW, Coquelin AW, Lu JKH (1987) Neuroendocrine control of luteinizing hormone secretion and reproductive function in spontaneously persistent-estrous aging rats. Biol Reprod 37: 1198-1206.
Pantić V (1980) Adenohypophyseal cell specificities and gonadal steroids In: Jutz M, Mckerns KW, eds. Synthesis and Release of Adenohypophyseal Hormones. New York: Plenum Press, pp. 335-362.
Poole MC, Kornegay WD (1982) Cellular distribution within the rat adenohypophysis: a morphometric study. Anat Rec 204: 45-53.
Roth GS (1990) Hormone/neurotransmitter action during aging: the calcium hypothesis of impaired signal transduction. Rev Biol Res Aging 4: 243-252.
Schneiter P, Raymond MJ, Lemarchand-Beraud T (1991) Age related alterations in prolactin binding sites in the female rat. Acta Endocrinol 124: 314-321.
Scorbrough K, Wise PM (1990) Age-related changes in pulsatile luteinizing hormone release precede the transition to estrous acyclicity and depend upon estrous cycle history. Endocrinology 126: 884-890.
Smith WA, Conn PM (1983). Causes and consequences of altered gonadotropin secretion in the aging rat. In: Walker RF, Cooper RL, eds. Experimental and Clinical Intervention in Aging. New York: Marcel Dekker, pp. 3-26.
Stojiljković SS, Tomić M (1996) GnRH induced calcium and current oscillations in gonadotrophs. Trends Endocrinol Metab 7: 379-384.
Tresguerres JAF, Esquifino AI (1981) Dissociation in the regulation of luteinizing hormone and follicle-stimulating hormone in a hyperprolactinemic rat model: interrelationships between gonadotrophin and prolactin control. J Endocrinol 90: 41-51.
Weibel ER (1979) Stereological Methods: Practical Methods of Biological Morphometry. Vol. 1. London: Academic Press, pp. 1-415.
Weibel ER, Gomez DM (1962) A principle for counting tissue structures random sections. J Appl Physiol 17: 343-348.
Wise PM (1982) Alterations in proestrous LH, FSH and prolactin surge in middle aged rats. Proc Soc Exp Biol Med 169: 348-354.
Wise PM, Camp C (1984) Changes in concentrations of estradiol nuclear receptors in preoptic area, medial basal hypothalamus, amygdala and old cycling rats. Endocrinology 114: 92-98.
Zorec R (1996) Calcium signaling and secretion in pituitary cells. TEM 7: 384-388.
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Lovren, M., Sekulić, M., Milošević, V. et al. Effects of Estradiol and Calcium on Gonadotrophic Cells in Middle-aged Female Rats. Histochem J 31, 671–676 (1999). https://doi.org/10.1023/A:1003899620578
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DOI: https://doi.org/10.1023/A:1003899620578