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Hypothetical interpretation of the calcium paradox in renin secretion
R Taugner1, R Nobiling, R Metz
1I. Physiologisches Institut, Universität Heidelberg, Federal Republic of Germany.
Abstract:
Most renin-positive cells of the preglomerular arteriole are intermediate in morphological appearence between smooth muscle cells and epithelioid cells. Intermediate cells contain, in addition to secretory granules, contractile proteins arranged as a sublemmal network. The paradoxical (inhibitory) role of calcium in renin secretion is explained, on the basis of these findings, by an increased tone of the sublemmal network; this might impair the preexocytotic access of renin granules to the cell membrane.
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