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Amino Acids

, Volume 15, Issue 1–2, pp 5–11 | Cite as

Changes in mediobasal hypothalamic dopamine and GABA release: A possible mechanism underlying taurine-induced prolactin secretion

  • Pablo Arias
  • H. Jarry
  • V. Convertini
  • M. Ginzburg
  • W. Wuttke
  • J. Moguilevsky
Full Papers

Summary

Taurine (Tau), a putative inhibitory amino acid neurotransmitter, has been shown to stimulate prolactin (PRL) release. Using ovariectomized, estrogen-replaced adult rats we investigated initially the effect of this amino acid, injected by different routes, on PRL secretion in vivo. Tau (100–500 mg/kg) had no effect on PRL release when given i.p.; 15 min after i.c.v. injection of Tau (3μmoles), a significant increase in serum PRL levels was observed (78 ± 9 ng/ml over basal levels, p < 0.01 vs. controls). In vitro (cultured anterior pituitary cells) PRL release was not affected by a 5 h incubation with Tau (10−3–10−8 M). Basal dopamine (DA) or gamma-aminobutyric acid (GABA) output from superfused mediobasal hypothalamic fragments (MBH) was not affected by Tau (10−3 M or 10−5 M). However, during stimulation with KCl (50mM), Tau (10−3 M) significantly lowered DA release, and increased GABA output. It is concluded that Tau acts at a central level to increase PRL secretion, most probably by modulating the hypothalamic release of neurotransmitters controlling lactotroph function.

Keywords

Amino acids Taurine Prolactin Dopamine GABA HPLC Hypothalamus 

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Copyright information

© Springer-Verlag 1998

Authors and Affiliations

  • Pablo Arias
    • 1
  • H. Jarry
    • 2
  • V. Convertini
    • 2
  • M. Ginzburg
    • 1
  • W. Wuttke
    • 2
  • J. Moguilevsky
    • 1
  1. 1.Departamento de Fisiología, Facultad de MedicinaUniversidad de Buenos AiresBuenos AiresArgentina
  2. 2.Abteilung klinische und experimentelle Endokrinologie FrauenklinikGeorg-August-UniversitätGöttingenGermany

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