MUSCARINIC REGULATION OF PHOSPHOLIPASE-A2 AND IODIDE FLUXES IN FRTL-5 THYROID-CELLS

被引：20

作者：

DIGIROLAMO, M ^{[1
]}

DARCANGELO, D ^{[1
]}

BIZZARRI, C ^{[1
]}

CORDA, D ^{[1
]}

机构：

[1] CONSORZIO MARIO NEGRI SUD,IST RIC FARMACOL MARIO NEGRI,CELLULAR & MOLEC ENDOCRINOL LAB,I-66030 SANTA MARIA IMBAR,ITALY

来源：

ACTA ENDOCRINOLOGICA | 1991年 / 125卷 / 02期

关键词：

D O I：

10.1530/acta.0.1250192

中图分类号：

R5 [内科学];

学科分类号：

1002 ; 100201 ;

摘要：

FRTL-5 thyroid cells express a muscarine receptor which inhibits the phospholipase C activity in a pirenzepine-insensitive manner. We here report that the cholinergic agonist carbachol decreases in these cells the steady-state iodide content, an effect correlated with the iodination of thyroglobulin and with thyroid hormone formation. Several signal pathways may be involved in this phenomenon since carbachol in addition to inhibiting phospholipase C, increased the arachidonic acid release and modified the adenylyl cyclase activity. In FRTL-5 cells, arachidonic acid is released via the direct stimulation of phospholipase A2 by a pirenzepine-sensitive muscarinic receptor coupled to a GTP binding protein sensitive to pertussis toxin. Regarding adenylyl cyclase, carbachol potentiated the thyrotropin-induced stimulation of the enzyme, whereas it did not affect the basal levels of cAMP. In vitro binding studies revealed the presence of two muscarinic binding sites. To summarize, the analysis of signal pathways and of in vitro binding sites indicates a complex muscarinic regulation of thyroid function, which includes the modulation of iodide fluxes.

引用

页码：192 / 200

页数：9

共 43 条

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