ISSN:
1438-2199
Keywords:
Amino acids
;
Taurine
;
Prolactin
;
Dopamine
;
GABA
;
HPLC
;
Hypothalamus
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
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.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01345276
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