Research Article| Volume 17, ISSUE 1, P5-16, July 1993

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Effects of oestrogen on hypothalamic β-endorphin in ovariectomized and old rats

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      Immunocytochemical β-endorphin (β-EP) staining and ultrastructual observations in the hypothalamus were compared in normal mature female rats, ovariectomized rats, and aged female rats. The effects of oestradiol benzoate (EB) on the hypothalamus were studied. The female Wistar rats were divided into seven groups, as follows: 40-day-old rats (Mature), 54-day-old rats ovariectomized at 40 days (Ovx), rats ovariectomized at 40 days and injected with 0.1 mg EB daily for 7 days (Ovx + e), rats ovariectomized and injected with one dose of 1 mg EB (Ovx + E), 500-day-old (Old), old rats injected with 0.1 mg EB daily for 7 days (Old + e), and old rats injected with 1 mg EB (Old + E). In the Ovx and Old groups, β-EP-positive cells in the arucuate nucleus were rarely seen, as compared with the Mature group. The staining of β-EP-positive cells in Ovx + e was slightly recovered and that in Ovx + E was almost completely recovered. However, no recovery of β-EP-positive cells was seen in the Old + e or Old + E groups. The number of nerve fibers in the median eminence were reduced in both the Ovx and Old groups, as compared with the Mature group. There was no relationship between changes in these numbers and oestrogen replacement in the Old group, but in the Ovx group oestrogen replacement brought about recovery of these numbers. The number of glial cells increased after oestrogen replacement in both the Ovx and Old groups. The frequency of giant mitochondria in the neurons in the arcuate nucleus decreased after oestrogen replacement in the Old group.


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        • Ganazzani AR
        • Petraclia F
        • Facchinetti F
        • Facchini V
        • Volpe A
        • Lessanarini G
        Increase of propiomelanocortin-related peptides during subjective menopausal flushes.
        Am J Obstet Gynecol. 1984; 149: 775-779
        • De Wied D
        • van Wimersma Greidanus TjB
        The neuropeptide concept and the menopause.
        in: 2nd edn. The climacteric and beyond. The Parthenon Publishing Group, Carnforth1987: 3-18
        • Ulrich AK
        • Gurleen SS
        • Felipe FC
        • Victor H
        • Henry CF
        Changes in beta-endorphin content in discrete areas of the hypothalamus throughout proestrus and diestrus of the rats.
        Life Sci. 1983; 33: 1443-1450
        • Kalra SP
        • Kalra PS
        Opioid-adrenergic-steroid connection in regulation of luteinizing hormone secretion in the rats.
        Neuroendocrinology. 1984; 38: 418-426
        • Sirinathsinghji DJS
        Regulation of lordosis behaviour in the female rat by corticotropin-releasing factor, β-endorphin/corticotropin and luteinizing hormone-releasing hormone neuronal systems in the medial preoptic area.
        Brain Res. 1986; 375: 49-56
        • Bridges RS
        • Ronsheim PM
        Immunoreactive beta-endorphin concentrations in brain and plasma during pregnancy in rats; possible modulation by progesterone and estradiol.
        Neuroendocrinology. 1987; 45: 381-388
        • Nohtomi A
        • Itoh M
        • Yufu N
        Effects of sulpiride treatment on the levels of immunoreactive β-endorphin in rat hypothalamic nuclei.
        Brain Res. 1984; 300: 152-156
        • Genazzani AR
        • Petraglia F
        • Facchinetti F
        • Genazzani AD
        • Bergamaschi M
        • Grasso A
        • Volpe A
        Effects of Org OD 14 on pituitary and peripheral β-endorphin in castrated rats and in post-menopausal women.
        Maturitas. 1987; (Suppl.): 35-48
        • Hashimoto S
        • Miwa M
        • Akasofu K
        • Nishida E
        Changes in 40 serum proteins of post-menopausal women.
        Maturitas. 1991; 13: 21-33
        • Nishida E
        • Akasofu K
        • Hashimoto S
        • Harada T
        • Uchide K
        • Nakagawa T
        • Tomimatsu N
        Any indication for androgen therapy?.
        in: 2nd edn. Progress in reproductive Biology and Medicine. 13. S. Karger, Basel1989: 86-94
        • Sarkar DK
        • Yen SSC
        Changes in β-endorphin-like immunoreactivity in pituitary portal blood during the estrous cycle and after ovariectomy in the rats.
        Endocrinology. 1985; 116: 2075-2079
        • Gambert SR
        • Garthwaite TL
        • Pontzer CH
        • Hagen TC
        Aged-related changes in central nervous system beta-endorphin and ACTH.
        Neuroendocrinology. 1980; 31: 252-255
        • Forman LJ
        • Marquis DE
        • Stevens R
        The effect of chronic estrogen treatment on immunoreactive β-endorphin levels in intact female rats.
        in: 2nd edn. Proc Soc Exp Biol Med. 179. 1985: 365-372
        • James CWF
        • Pia L
        • Peter P
        Immunocyto chemical localization of β-endorphin-containing neurons in the rat brain.
        Neuroendocrinology. 1981; 33: 28-42
        • De Groot J
        The rat forebrain in stereotactic cordinates.
        Trans R Neth Acad Sci. 1959; 52: 1-12
        • Genazzani AR
        • Trentini GP
        • Petraglia F
        • De Gaetani CF
        • Criscuolo M
        • Ficarra G
        • De Ramundo BM
        Estrogens modulate the circadian rhythm of hypothalamic β-endorphin contents in female rats.
        Neuroendocrinology. 1990; 52: 221-224
        • Erlik Y
        • Meldrum DR
        • Judd HL
        Estrogen levels in postmenopausal women with hot flashes.
        Obstet Gynecol. 1982; 59: 403-407
        • Pardridge WM
        • Mietus LJ
        Transport of steroid hormones through the rat blood-brain barrier: Primary role of albumin-bound hormone.
        J Clin Invest. 1979; 64: 145-154
        • Genazzani AR
        • Petraglia F
        • Bergamaschi M
        • Genazzani AD
        • Facchinetti F
        • Volpe A
        Progesterone and progestins modulate β-endorphin concentrations in the hypothalamus and in the pituitary of castrated and female rats.
        Gynecol Endocrinol. 1987; 1: 61-69
        • Genazzani AR
        • Petraglia F
        • Mercuri N
        • Brilli G
        • Genazzani AD
        • Bergamaschi M
        • Deramundo BM
        • Volpe A
        Effect of steroid hormones and antihormons on hypothalamic β-endorphin concentrations in intact and castrated rats.
        J Endocrinol Invest. 1990; 13: 91-96
        • Le S
        • Chung CJ
        • Parkening TA
        Effect of ovariectomy and estrogen replacement on hypothalamic, pituitary and peripheral blood β-endorphin levels in the rat.
        Neuropeptides. 1991; 20: 175-180
        • Forman LJ
        • Estilow S
        Estrogen influences the effect of immobilization stress on immunoreactive β-endorphin levels in the female rat pituitary.
        in: 2nd edn. Proc Soc Exp Biol Med. 187. 1988: 190-196
        • Ronald P
        • Hammer JR
        • Robert SB
        Preoptic area opioids and opiate receptors increase during pregnancy and decrease during lactation.
        Brain Res. 1987; 420: 48-56
        • Brawer JR
        • Ruf KB
        • Naftolin F
        The effects of estradiol-induced lesions of the arcuate nucleus on gonadotropin release in response to preoptic stimulation in the rat.
        Neuroendocrinology. 1980; 30: 144-149
        • Brawer JR
        • Schipper H
        • Naftolin F
        Ovary-dependent degeneration in the hypothalamic arcuate nucleus.
        Endocrinology. 1980; 107: 274-279
        • Shivers BD
        • Harlan RE
        • Pfaff DW
        A subset of neurons containing immunoreactive prolactin is a target for estrogen regulation of gene expression in rat hypothalamus.
        Neuroendocrinology. 1989; 49: 23-27
        • Olster DH
        • Blaustein JD
        Immunocytochemical colocalization of progestin receptors and β-endorphin or enkephalin in the hypothalamus of female guinea pigs.
        J Neurobiol. 1990; 21: 768-780
        • Cotman CW
        • Scheff SW
        Synaptic growth in aged animals.
        in: Cherken A Physiology and Cell Biology of Aging. Raven Press, New York1979: 109-120
        • Schipper H
        • Brawer JR
        • Nelson JF
        • Felicio LS
        • Finch CE
        The role of gonads in the histologic aging of the hypothalamic arcuate nucleus.
        Biol Reprod. 1981; 25: 413-419
        • Sato T
        Morphological and biochemical analysis on autofluorescent granules in various tissues and cells of the rats under several nutritional conditions.
        Mech Ageing Dev. 1988; 43: 229-238
        • Ne'eman Z
        • Pinson A
        Oxygen and extracellular fluid restriction in cultured heart cells: electron microscopy studies.
        Cardiovasc Res. 1990; 24: 555-559
        • Regius O
        • Rajczy K
        • Gergely I
        • Borzsonyi L
        • Lengyel E
        • Vargha P
        The effect of smoking on peripheral blood lymphocytes and some immunological parameters in old age.
        Z Gerontol. 1990; 23: 163-167