Agonist-induced contraction of reconstituted fiber of cultured smooth muscle cells derived from rat middle cerebral artery

• Published in: Japanese Journal of Pharmacology 2001, Vol.85 (suppl.2), p.285-285
• Main Authors: Yoshitaka Takatou, Kazuhiko Oishi, Masaatsu Uchida
• Format: Article
• Language: Japanese
• ISSN: 0021-5198

We have developed a method of reconstituting hybrid smooth muscle (SM) fibers that retain capabilities of responding to typical contractile agonists to produce isometric contraction (K.Oishi et al., Am. J. Physiol., 279, C1432-42, 2000). In this study, SM cells were isolated and cultured from rat middle cerebral artery. String-shaped SM fibers were prepared in rectangular wells by thermal gelation of collagen and cultured SM cells. Within a day after casting the gel, the cells and collagen formed a thin fiber spanning the two poles to the bottom of rectangular wells. After 7 days of incubation, isometric contractions were studied. The fibers contracted in response to KCl (70 mM), serotonin (10 μM), endothelin-1 (10 nM), prostaglandin F2α (1 μM), angiotensin II (100 nM) and Ca^2+ ionophore A23187 (5 μM), but not acetylcholine (100 μM) and histamine (100 μM). Serotonin-induced contractions were partially inhibited by nifedipine(2 μM), and completely abolished by the myosin light chain kinase inhibitor ML-9 (30 μM), the Rho kinase inhibitor Y-27632 (1 μM), db-cAMP (100 μM), 8-Br-cGMP (100 μM), and papaverine (10 μM). These results suggest that both contractility and pharmacological responsiveness typical for cerebrovascular smooth muscles were preserved in those fibers.