The mode of action of bromocriptine

Autor: I. Gloger, Avraham Hochberg, Nathan de-Groot, Joseph G. Schenker, D. Weinstein, R. Folman, J.H. Slonim
Rok vydání: 1981
Předmět:
Zdroj: FEBS letters. 126(1)
ISSN: 0014-5793
Popis: 1. Introduction Bromocriptine, an ergot alkaloid and dopamine agonist, is the treatment of choice for the induction of ovulation and pregnancy in cases of infertility due to both functional and organic hyperprolactinemia, the latter being due to prolactin secreting pituitary adenomas. It was found that 5-22% of the popula- tion harbour pituitary adenomas [ 1,2]. Bromocrip- tine has also been useful in the treatment of the symp- tomatic enlargement of pituitary adenomas during pregnancy as documented by tumor size reduction 131. Bromocriptine crosses the placenta and enters the fetal circulation reducing prolactin secretion in both maternal and fetal pituitaries [4]. At the level of the pituitary lactotroph there is evidence of the existence of dopamine receptors on the cell membrane and that bromocriptine acts as a dopamine receptor agonist [S]. It has been suggested that bromocriptine acts primarily on prolactin secretion, and that the subse- quent accumulation of prolactin within the pituitary inhibits translation and possibly transcription, by an intracellular negative-feedback mechanism [6]. The results of our investigation indicate that bromocrip- tine itself may act by inhibiting transcription. 2. Materials and methods L-[4,5-3H]Leucine (spec. act. 30.2 Ci/mmol and [5,6-3H]uridine (spec. act. 40.3 Ci/mmol) were pur- chased from Kamag, Negev. [‘*‘I] Iodine (carrier free) was purchased from Radiochemical Centre,Amersham. Rat prolactin and corresponding antiserum were sup- plied by the NlAMDD hormone distributors program
Databáze: OpenAIRE
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