Advertisement

Journal of Endocrinological Investigation

, Volume 25, Issue 2, pp 96–100 | Cite as

Interactions between GABAergic and aminoacidergic pathways in the control of gonadotropin and GH secretion in pre-pubertal female rats

  • L. Pinilla
  • L. C. González
  • M. Tena-Sempere
  • Enrique Aguilar
Original Article

Abstract

Present experiments were carried out in 23-day-old female rats to analyze the interaction between excitatory amino acids (EAAs) and gamma-aminobutyric acid (GABA) in the control of gonadotropin and GH secretion. For this purpose, serum concentrations of LH, FSH and GH were measured after injection of different agonists of EAA receptor subtypes [N-methyl-D-aspartate (NMDA); kainic acid (KA), ±α-amino-3-hydroxy- 5-methylisoxazole-4-propionic acid (AMPA)], antagonists of GABA receptors (bicuculline, phaclofen) or the combined administration of both types of drugs. The results obtained indicated that: 1) GABA has a minor physiological role in the control of LH and GH secretion, since neither LH nor GH serum concentrations changed after administration of bicuculline (antagonist of GABAA receptors) or phaclofen (antagonist of GABAB receptors); 2) GABA has a sex-specific physiological role in the control of FSH secretion in female rats, in which FSH secretion increases after phaclofen administration; 3) GH secretion was enhanced after administration of NMDA, KA and AMPA, while LH increased only after activation of NMDA receptors; 4) the stimulatory effect of NMDA on LH secretion was counteracted by administration of phaclofen; and 5) bicuculline and phaclofen reduced the ability of NMDA and AMPA to stimulate GH secretion. In conclusion, present experiments evidenced a physiological role of GABA, mediated by GABAB receptors, in the control of FSH secretion and a cross-talk between excitatory and inhibitory amino acids in the control of anterior pituitary secretion.

Key-words

GABA NMDA KA AMPA gonadotropins GH 

Key-words

GABA NMDA KA AMPA gonadotropins GH 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Neill J.D., Nagy G.M. Prolactin secretion and its control. In: Knobil E., Neill J.D. (Eds.), The physiology of reproduction. Raven Press, New York, 1994, p. 1833.Google Scholar
  2. 2.
    Brann D.W., Mahesh V.B. Excitatory amino acids: evidence for a role in the control of reproduction and anterior pituitary function. Endocr. Rev. 1998, 18: 678–700.Google Scholar
  3. 3.
    Tena-Sempere M., Pinilla L., Gonzalez L.C., et al. Regulation of growth hormone (GH) secretion by different glutamate receptor subtypes in the rat. Amino Acids 2000, 18: 1–16.PubMedCrossRefGoogle Scholar
  4. 4.
    Gonzalez L.C., Pinilla L., Tena-Sempere M., et al. Regulation of growth hormone secretion by amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptors in infantile, prepubertal, and adult male rats. Endocrinology 1999, 140: 1279–1284.PubMedGoogle Scholar
  5. 5.
    Pinilla L., Tena-Sempere M., Aguilar E. Sexual differences in the role of kainate receptors in controlling gonadotrophin secretion in prepubertal rats. J. Reprod. Fert. 1998, 113: 269–273.CrossRefGoogle Scholar
  6. 6.
    Gonzalez L.C., Pinilla L., Tena-Sempere M., et al. Role of AMPA receptors in the control of anterior pituitary secretion in prepubertal female rats. J. Endocrinol. 1999, 162: 417–422.PubMedCrossRefGoogle Scholar
  7. 7.
    Gonzalez L.C., Pinilla L., Tena-Sempere M., et al. Regulation of prolactin secretion by a-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptors in male rats. J. Endocrinol. 2000, 166: 669–675.PubMedCrossRefGoogle Scholar
  8. 8.
    Abbud R., Smith M.S. Differences in the luteinizing ho rmone and prolactin responses to multiple injections of kainate, as compared with N-methyl-D,L,-aspartate, in cycling rats. Endocrinology 1991, 129: 3254–3258.PubMedCrossRefGoogle Scholar
  9. 9.
    Carbone S., Szwarcfarb B., Rondina D., et al. Effect of ovarian hormones on the prolactin response to excitatory amino acid system during sexual maturation. Neuroendocrinol. Lett. 1994, 16: 247–255.Google Scholar
  10. 10.
    Luderer U., Strobl F.J., Levine J.E., et al. Differential gonadotropin responses to N-methyl-D,L,-aspartate in metestrous, proestrous, and ovariectomized rats. Biol. Reprod. 1993, 48: 857–866.PubMedCrossRefGoogle Scholar
  11. 11.
    Pinilla L., Gonzalez D., Tena-Sempere M., et al. Effects of Nmethyl-aspartate and kainic acid on prolactin secretion in prepubertal female rats. Eur. J. Endocrinol. 1996, 135: 464–468.PubMedCrossRefGoogle Scholar
  12. 12.
    Pinilla L., Tena-Sempere M., Aguilar R., et al. Effects of Nmethyl-aspartic acid and kainic acid on prolactin secretion in hyper-and hypoprolactinaemic conditions. Eur. J. Endocrinol. 1998, 138: 460–466.PubMedCrossRefGoogle Scholar
  13. 13.
    McCann S.M, Rettori V. Gamma amino butyric acid (GABA) controls anterior pituitary hormone secretion. In: Racagni G., Donoso A.O. (Eds.), GABA and endocrine function. Raven Press, New York, 1986, p. 173.Google Scholar
  14. 14.
    Donoso A.O., López F.J., Negro-Vilar A. Cross-talk between excitatory and inhibitory amino acids in the regulation of luteinizing hormone-releasing hormone secretion. Endocrinology 1992, 131: 1559–1561.PubMedGoogle Scholar
  15. 15.
    Scacchi P., Carbone S., Szwarcfarb B., et al. Interactions between GABAergic and serotoninergic systems with excitatory amino acid neurotransmission in the hypothalamic control of gonadotropin secretion in prepubertal female rats. Brain Res. Dev. 1998, 105: 51–58.CrossRefGoogle Scholar
  16. 16.
    Pinilla L., Gonzalez L.C., Tena-Sempere M., et al. Cross-talk between excitatory and inhibitory amino acids in the regulation of growth hormone secretion in neonatal rats. Neuroendocrinology 2001, 73: 62–67.PubMedCrossRefGoogle Scholar
  17. 17.
    Greenwood F.C, Hunter W.M., Glover J.S. The preparation of 131I-labelled human growth hormone of high specific radioactivity. Biochem. J. 1963, 89: 114–123.PubMedCentralPubMedGoogle Scholar
  18. 18.
    Hood S.C., Schwartz N.B. Sex differences in serum luteinizing hormone postgonadectomy in the rat: role of gammaaminobutyric acidergic inhibition. Endocrine 2000, 12: 35–40.PubMedCrossRefGoogle Scholar
  19. 19.
    Hartman R.D., He J.R., Barraclough C.A. Gamma-aminobutyric acid-A and B-receptor antagonists increase luteinizing hormone-releasing hormone neuronal responsiveness to intracerebroventricular norepinephrine in ovariectomized estrogen-treated rats. Endocrinology 1990, 127: 1336–1345.PubMedCrossRefGoogle Scholar
  20. 20.
    Lux-Lantos V., Rey E., Libertun C. Activation of GABAB receptors in the anterior pituitary inhibits prolactin and luteinizing hormone secretion. Neuroendocrinology 1992, 56: 687–693.PubMedCrossRefGoogle Scholar
  21. 21.
    Moguilevski J.A., Carbone S., Szwarcfarb B., et al. Sexual maturation modifies the GABAergic control of gonadotropin secretion in female rats. Brain Res. 1991, 563: 12–16.CrossRefGoogle Scholar
  22. 22.
    Justo S.N., Rossano G.L., Szwarcfarb B., et al. Effect of serotoninergic system on FSH secretion in male and female rats: Evidence for stimulatory and inhibitory actions. Neuroendocrinology, 1989, 50: 382–386.PubMedCrossRefGoogle Scholar
  23. 23.
    Moguilevski J.A., Faigon M.R., Rubio M.C., et al. Sexual differences in the effect of serotonin on LH secretion in rats. Acta Endocrinol. (Copenh.) 1985, 109: 320–325.Google Scholar
  24. 24.
    McCann S.M., Minezuma H., Samson W.K., et al. Differential hypothalamic control of FSH secretion: A review. Psychoneuroendocrinology 1983, 8: 299–308.PubMedCrossRefGoogle Scholar
  25. 25.
    Lumpkin M.D., Moltz J.H., Yu W.H., et al. Purification of FSHreleasing factor: its dissimilarity from LHRH of mammalian, avian and piscin origin. Brain Res. Bull. 1987, 18: 175–181.PubMedCrossRefGoogle Scholar
  26. 26.
    Wildt L., Hausler A., Marshall G., et al. Frequency and amplitude of gonadotropin-releasing hormone stimulation and gonadotropin secretion in the rhesus monkey. Endocrinology 1981, 109: 376–385.PubMedCrossRefGoogle Scholar
  27. 27.
    Clarke I.J., Cummins J.T., Findlay J.K., et al. Effects on plasma luteinizing hormone and follicle-stimulating hormone of varying the frequency and amplitude of gonadotropin-releasing hormone pulses in ovariectomized ewes with hypothalamic-pituitary disconnection. Neuroendocrinology 1984, 39: 214–221.PubMedCrossRefGoogle Scholar
  28. 28.
    Strobl F.J., Luderer U., Besecke L., et al. Differential gonadotropin responses to N-methyl-D,L-aspartate in intact and castrated male rats. Biol. Reprod. 1993, 48: 867–873.PubMedCrossRefGoogle Scholar

Copyright information

© Italian Society of Endocrinology (SIE) 2002

Authors and Affiliations

  • L. Pinilla
    • 1
  • L. C. González
    • 1
  • M. Tena-Sempere
    • 1
  • Enrique Aguilar
    • 1
  1. 1.Department of Physiology, Faculty of MedicineCórdoba UniversityCórdobaSpain

Personalised recommendations