Isolation of smooth muscle cells from swine carotid artery by digestion with papain.

A new method is described for the preparation of viable, elongated smooth muscle cells from the swine carotid artery. Cells were prepared by papain digestion of pressurized arteries in calcium-free solution. After digestion, the arteries were everted, and fine strips were teased from the intimal surface of the media in calcium-free solution, releasing single cells. Viability was assessed by exclusion of trypan blue and by appearance under phase-contrast microscopy. By these criteria, approximately 20% of the isolated cells were viable. The most distinguishing and unexpected characteristic of these cells was their length. Mean length of the relaxed viable cells was 240.4 +/- 47.4 microns (SD, n = 76), which is much longer than previously reported for arterial smooth muscle cells. Calcium (1.6 mM) caused most of the viable cells to contract slightly, and the mean cell length in calcium was 194.4 +/- 57.7 microns. Cells in 1.6 mM calcium contracted substantially in response to 10 microM histamine or the calcium ionophore A23187 (10 microM), demonstrating that histamine receptors and the contractile apparatus were still functional.