Growth‐related variation of α2‐adrenergic receptivity in the HT 29 adenocarcinoma cell‐line from human colon

• Published in: FEBS letters Vol. 184; no. 1; pp. 82 - 86
• Main Authors: Paris, H., Bouscarel, B., Cortinovis, C., Murat, J.C.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier 06.05.1985
• Subjects: [3H ] Clonidine; Biological and medical sciences; Catecholamines; Cell culture; Cell receptors; Cell structures and functions; Cyclic AMP; Fundamental and applied biological sciences. Psychology; HT 29 cell-line; Molecular and cellular biology; α2-Adrenoceptor; Adenylate cyclase; Cell culture; Regulation(control); Enzyme; Cyclic AMP; Α2-Adrenergic receptor; Tumor; Binding site; Colon; Tumor cell
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(85)80658-X

The human colon adenocarcinoma cell‐line HT 29 has been shown to possess functional α2‐adrenergic receptors. Here, [3H] clonidine was used as radioligand to study the evolution of α2‐adrenergic receptivity during the time course of HT 29 cell culture. Scatchard analysis of the saturation curves indicates that the number of [3H]clonidine binding sites increases throughout the 17 day culture period. The maximal number of α2adrenoceptors is found during the stationary phase of growth, when cell density is high and mitotic rate low. Moreover, the use of adrenaline and clonidine as α2‐adrenergic agonists reveals a relationship between the number of receptors and the intensity of the biological effect associated with their stimulation (inhibition of the VIP‐induced cyclic AMP accumulation).