Pyridoxine (B6)-induced inhibition of prolactin release in the female rat

A. R C Harris, M (Susan) Smith, S. Alex

Research output: Contribution to journalArticle

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Abstract

The present studies were carried out to determine whether pyridoxine (B6) inhibits PRL release in the rat and to define its site of action. Adult female rats were injected with 50 mg B6 of diluent (C) ip at 1200 hr on proestrus. B6 prevented the increase in PRL secretion normally observed at 1300 hr and this inhibition was prolonged until at least 1500 hr by a second injection of B6 at 1400 hr. All B6 treated and control animals had normal proestrous LH surges and ovulated the next day. To determine whether the inhibitory effect of B6 on PRL release was due to enhanced dopamine synthesis or to a direct effect on the pituitary, ovariectomized rats were treated with a potent inhibitor of dopamine synthesis, α methyl p tyrosine (α MPT). The administration of B6 either with or 4 hr after α MPT significantly decreased the PRL rise observed in animals treated with α MPT alone. B6 also significantly suppressed the TRH induced PRL rise in both α MPT treated and normal rats, but had no effect on the TRH induced rise in plasma TSH concentration. These studies demonstrate that pharmacological doses of B6 reduce the proestrous PRL surge and that this reduction may be at least partially due to a direct effect on the pituitary, inasmuch as B6 decreased the PRL rise after α MPT and/or TRH administration.

Original languageEnglish (US)
Pages (from-to)362-366
Number of pages5
JournalEndocrinology
Volume102
Issue number2
StatePublished - 1978
Externally publishedYes

Fingerprint

Pyridoxine
Prolactin
Tyrosine
Dopamine
Proestrus
Pharmacology
Injections

ASJC Scopus subject areas

  • Endocrinology
  • Endocrinology, Diabetes and Metabolism

Cite this

Harris, A. R. C., Smith, M. S., & Alex, S. (1978). Pyridoxine (B6)-induced inhibition of prolactin release in the female rat. Endocrinology, 102(2), 362-366.

Pyridoxine (B6)-induced inhibition of prolactin release in the female rat. / Harris, A. R C; Smith, M (Susan); Alex, S.

In: Endocrinology, Vol. 102, No. 2, 1978, p. 362-366.

Research output: Contribution to journalArticle

Harris, ARC, Smith, MS & Alex, S 1978, 'Pyridoxine (B6)-induced inhibition of prolactin release in the female rat', Endocrinology, vol. 102, no. 2, pp. 362-366.
Harris, A. R C ; Smith, M (Susan) ; Alex, S. / Pyridoxine (B6)-induced inhibition of prolactin release in the female rat. In: Endocrinology. 1978 ; Vol. 102, No. 2. pp. 362-366.
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