In:
American Journal of Physiology-Endocrinology and Metabolism, American Physiological Society, Vol. 280, No. 4 ( 2001-04-01), p. E608-E615
Abstract:
Pituitary folliculostellate cells (FSCs) are thought to partially inhibit pituitary hormone secretion through a paracrine mechanism. In this process, one of the important questions is what factors regulate the function of FSCs. Because ACh is synthesized in and possibly released from the corticotrophs and lactotrophs, we examined whether FSCs respond to ACh by the method of Ca 2+ imaging in primary cultured FSCs from male Wistar rats. ACh (30 nM-3 μM) increased intracellular calcium concentration ([Ca 2+ ] i ) of FSCs in a concentration-dependent manner, with an initial rapid rise followed by a relatively sustained increase. The complete block of the response by atropine and pirenzepine suggests involvement of muscarinic receptors. Depletion of the stored Ca 2+ by thapsigargin blocked the response completely. Blockers of phospholipase C, U-73122 and neomycin, suppressed significantly the rise of [Ca 2+ ] i . These results suggest that ACh increases [Ca 2+ ] i in FSCs by activating phospholipase C, presumably through activation of M 1 receptors. The rise in [Ca 2+ ] i could trigger a variety of Ca 2+ -dependent cellular processes, including the synthesis and release of bioactive substances, which in turn act on endocrine cells.
Type of Medium:
Online Resource
ISSN:
0193-1849
,
1522-1555
DOI:
10.1152/ajpendo.2001.280.4.E608
Language:
English
Publisher:
American Physiological Society
Publication Date:
2001
detail.hit.zdb_id:
1477331-4
SSG:
12
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