Premium
F.9 Embryonal carcinoma cell calcitonin autocrine system: Correlation between immunoreactive calcitonin secretion and calcitonin receptor number
Author(s) -
Binet Elisabeth,
Laurent Pascale,
EvainBrion Daniele
Publication year - 1985
Publication title -
journal of cellular physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.529
H-Index - 174
eISSN - 1097-4652
pISSN - 0021-9541
DOI - 10.1002/jcp.1041240218
Subject(s) - calcitonin , receptor , autocrine signalling , endocrinology , medicine , secretion , retinoic acid , biology , cell culture , adrenomedullin , heterologous , microbiology and biotechnology , biochemistry , genetics , gene
Mouse teratocarcinoma cells in culture offer an in vitro system to study the initial steps of embryogenesis. It has been suggested that, at such early stages, cell functions are regulated by an autocrine process in which embryonic cells produce factors that in turn act on themselves. F.9 cells possess specific membrane receptors for calcitonin (CT) (120 fmol/mg of protein, Ka, = 3.5 × 10 8 M −1 ). These cells produce CT detected by heterologous radioimmunossay in serum‐free culture‐conditioned medium (75 pg/10 7 cells/12 h). When F.9 cells are incubated in serum‐free medium, CT binding and secretion concomitantly drop by 50% within the first 2 h, then increase progressively to an upper plateau after the sixth hour. Preincubation with 10 −6 M CT leads to disappearance of CT receptors and CT secretion in the culture medium up to 6 h. Avoiding accumulation of CT in the medium by a continuous flow rate for 6 h leads to a progressive decrease of CT receptors. In addition, retinoic acid treatment of cells induces a parallel progressive decrease of CT receptor number and of total CT synthesis. These results suggest a reciprocal regulation of CT receptors and CT secretion, or a close relationship between their regulations.