Download PDF
Horm Metab Res 2006; 38(4): 219-224
DOI: 10.1055/s-2006-925330
Original
© Georg Thieme Verlag KG Stuttgart · New York

Changes of Sex Hormone-binding Globulin/SHBG Expression in the Hypothalamo-hypophyseal System of Rats During Pregnancy, Parturition and Lactation

E.  Sendemir1, 2 , Z.  Herbert2, 3 , J.  D.  Caldwell4 , G.  F.  Jirikowski2
  • 1Department of Anatomy, Uludag University, School of Medicine, Bursa, Turkey
  • 2Department of Anatomy II, Friedrich-Schiller University, Jena, Germany
  • 3Department of Biology II, Neurobiology, Ludwig Maximilian University, Munich, Germany
  • 4Department of Biomedical Sciences, University of Illinois College of Medicine, Rockford, IL, USA
Further Information

Publication History

Received 14 July 2005

Accepted after revision 15 February 2006

Publication Date:
15 May 2006 (online)

Also available at
    Permissions and Reprints

Abstract

Sex hormone-binding globulin (SHBG) is expressed in hypothalamic magnocellular neurons. High co-localization rates of SHBG with oxytocin have been observed in the hypothalamus, indicating that SHBG plays a role in pregnancy, parturition and lactation. Further studies have shown that hypothalamic SHBG expression is malleable to changing steroid conditions. In this study, we have examined SHBG levels in the supraoptic and paraventricular hypothalamic nuclei and in the posterior pituitary lobe of late pregnant, parturient and early lactating rats by in situ hybridization, immunocytochemistry, and ELISA. Immunocytochemical and biochemical analysis showed that the SHBG levels increased during late pregnancy in hypothalamic nuclei. During parturition, SHBG levels fell in the magnocellular nuclei but increased in the posterior pituitary lobe. SHBG levels increase again during lactation. At day six of lactation, there was no significant difference in SHBG levels compared to normal cycling female rats, which served as control in this study. In situ hybridization showed increased SHBG mRNA signal during late pregnancy. The highest SHBG expression was observed during parturition. Our data indicate that hypothalamic SHBG expression changes during pregnancy, parturition and lactation, parallel to ovarian steroid and co-localized OT levels. This may in part be linked to known steroid actions on synthesis and secretion of magnocellular hypothalamic peptide hormones, important for the control of parturition and lactation.

Key words

Supraoptic nucleus - paraventricular nucleus - parturition - magnocellular hypothalamic neurons - steroid actions - oxytocin

References

  • 1 Herbert Z, Jirikowski G F, Petrusz P, Englof I, Caldwell J D. Distribution of androgen binding globulin in the rat hypothalamo-hypophysial system, co-localization with oxytocin.  Brain Res. 2003;  992 151-158
    CrossrefPubMedGoogle Scholar
  • 2 Herbert Z, Gothe S, Caldwell J D, Petrusz P, Peuckert P, Jirikowski G F. Identification of sex hormone-binding globulin in the human hypothalamus.  Neuroendocrinol. 2005;  81 287-293
    PubMedGoogle Scholar
  • 3 Wang Y M, Bayliss D A, Millhorn D E, Petrusz P, Joseph D R. The androgen-binding protein gene is expressed in male and female rat brain.  Endocrinology. 1990;  127 3124-3130
    CrossrefPubMedGoogle Scholar
  • 4 Leng G, Caquineau C, Sabatier N. Regulation of oxytocin secretion.  Vitam Horm. 2005;  71 27-58
    PubMedGoogle Scholar
  • 5 Herbert Z, Pollak E, Molnar L, Caldwell J D, Jirikowski G F. Co-transport of sex hormone binding globulin/SHBG with oxytocin in transport vesicles of the hypothalamo-hypophyseal system.  Horm Metab Res. 2006;  in press
    PubMedGoogle Scholar
  • 6 Caldwell J D, Moe B D, Hoang J, Nguyen T. Sex hormone binding globulin stimulates female sexual receptivity.  Brain Res. 2000;  874 24-29
    CrossrefPubMedGoogle Scholar
  • 7 Caldwell J D. Evidence of sex hormone binding globulin binding sites in the medial preoptic area and hypothalamus.  Horm Metab Res. 2001;  33 7-9
    Article in Thieme ConnectPubMedGoogle Scholar
  • 8 Fortunati N. Sex hormone-binding globulin: Not only a transport protein. What news is around the corner?.  J Endocrinol Invest. 1999;  22 223-234
    PubMedGoogle Scholar
  • 9 Danzo B J, Cooper T G, Orgebin-Crist M C. Androgen binding protein (ABP) in fluids collected from the rete testis and cauda epididymidis of sexually mature and immature rabbits and observations on morphological changes in the epididymis following ligation of the ductuli efferentes.  Biol Reprod. 1977;  17 64-77
    CrossrefPubMedGoogle Scholar
  • 10 Rosner W, Hryb D J, Khan M S, Nakhla A M, Romas N A. Sex hormone-binding globulin mediates steroid hormone signal transduction at the plasma membrane.  J Steroid Biochem Mol Biol. 1999;  69 481-485
    CrossrefPubMedGoogle Scholar
  • 11 Jirikowski G F, Ramalho Ortigao F J, Lindl T, Seliger H. Immunocytochemistry of 5-bromo-2’-deoxyuridine labeled oligonucleotide probes. A novel technique for in situ hybridization.  Histochemistry. 1989b;  91 51-53
    CrossrefPubMedGoogle Scholar
  • 12 Becchis M, Sullivan P M, Ordronneau P, Petrusz P, Joseph D R. Distribution of immunoreactive androgen-binding protein/sex hormone-binding globulin in tissues of the fetal rat.  Steroids. 1996;  61 392-400
    CrossrefPubMedGoogle Scholar
  • 13 Reventos J, Hammond G L, Crozat A, Brooks D E, Gunsalus G L, Bardin C W, Musto N A. Hormonal regulation of rat androgen-binding protein (ABP) messenger ribonucleic acid and homology of human testosterone-estradiol-binding globulin and ABP complementary deoxyribonucleic acids.  Mol Endocrinol. 1988;  2 125-132
    PubMedGoogle Scholar
  • 14 Jirikowski G F. SOFIA, A Superior approach for high sensitivity immunoassays.  Biomed Prod. 1993;  7193 105-109
    PubMedGoogle Scholar
  • 15 Gao G, Herbert Z, Kong J, Wu D, Gabrielson N, Jirikowski G F, Caldwell J D. Estradiol control of estradiol binding proteins and levels in the medial preoptic area, medial hypothalamus and pituitary.  Neuroendocrinology. 2003;  78 61-71
    CrossrefPubMedGoogle Scholar
  • 16 Wang Y M, Bayliss D A, Millhorn D E, Petrusz P, Joseph D R. The androgen-binding protein gene is expressed in male and female rat brain.  Endocrinol. 1990;  127 3124-3130
    CrossrefPubMedGoogle Scholar
  • 17 Jirikowski G F, Herbert Z, Petrusz P, Sendemir E, Caldwell J D. Co-expression of vasopressin and androgen-binding protein in the rat hypothalamus.  J Chem Neuroanat. 2005;  29 233-237
    CrossrefPubMedGoogle Scholar
  • 18 Jirikowski G F, Caldwell J D, Pedersen C A, Stumpf W E. Estradiol influences oxytocin-immunoreactive brain systems.  Neuroscience. 1988;  25 237-248
    CrossrefPubMedGoogle Scholar
  • 19 Caldwell J D, Hoefle S, Englof I. Sex hormone binding globulin facilitates female sexual receptivity except when coupled to dihydrotestosterone.  Brain Res. 2002;  948 102-107
    CrossrefPubMedGoogle Scholar
  • 20 Caldwell J D, Moe B D. Conjugated estrodiol increases female sexual receptivity in response to oxytocin infused into the medial preoptic area and medial basal hypothalamus.  Horm Behav. 1999;  35 38-46
    PubMedGoogle Scholar
  • 21 Buijs R M, de Vries G J, van Leeuwen F W, Swaab D F. Vasopressin and oxytocin: distribution and putative functions in the brain. Prog.  Brain Res. 1983;  60 115-122
    PubMedGoogle Scholar
  • 22 Florio P, Woods R J, Genazzani A R, Lowry P J, Petraglia F. Changes in amniotic fluid immunoreactive corticotropin-releasing factor (CRF) and CRF-binding protein levels in pregnant women at term and during labor.  J Clin Endocrinol Metab. 1997;  82 835-838
    CrossrefPubMedGoogle Scholar
  • 23 Stumpf W E, Sar M, Keefer D A. Atlas of estrogen target cells in the rat brain. In: Stumpf WE, Grant LD (eds) Anatomical Neuroendocrinology. Basel; Karger 1975: 104-119
    Google Scholar
  • 24 Perez S E, Chen E Y, Mufson E J. Distribution of estrogen receptor alpha and beta immunoreactive profiles in the postnatal rat brain.  Brain Res Dev Brain Res. 2003;  145 117-139
    PubMedGoogle Scholar
  • 25 Vigh B, Vigh-Teichmann I. Comparison of the ultrastructure of cerebrospinal-fluid-contact neurons and pinealocytes in mammals.  Verh Anat Ges. 1975;  69 453-461
    PubMedGoogle Scholar
  • 26 Fassler R, Schwarz S, Pohl P. Demonstration of sex hormone binding globulin in human cerebrospinal fluid.  Clin Endocrinol (Oxf). 1985;  23 349-359
    PubMedGoogle Scholar
  • 27 Jirikowski G F, Caldwell J D, Pilgrim C, Stumpf W E, Pedersen C A. Changes in immunostaining for oxytocin in the forebrain of the female rat during late pregnancy, parturition and early lactation.  Cell Tissue Res. 1989a;  256 411-417
    PubMedGoogle Scholar
  • 28 Ganten D, Pfaff D. Neurobiology of oxytocin. In: Ganten D, Pfaff D (eds) Current topics in neuroendocrinology. Heidelberg; Springer 1986: 1-175
    Google Scholar
  • 29 Breuner C W, Orchinik M. Plasmabinding proteins as mediators of Corticosteroid action in vertebrates.  J Endocrinol.. 2002;  175 99-112
    CrossrefPubMedGoogle Scholar

Gustav F. Jirikowski

FSU · Institut für Anatomie · Anatomie II

Teichgraben 7 · 07743 Jena · Germany ·

Phone: +49 (3641) 93 85 53

Fax: +49 (3641) 93 85 52

Email: gjir@mti.uni-jena.de

      >