A method for isolating adult and neonatal airway smooth muscle cells and measuring shortening velocity

Physiology Department, Temple University School of Medicine, Philadelphia, Pennsylvania 19140 Methods are described for isolating smooth muscle cells from the tracheae of adult and neonatal sheep and measuring the single-cell shortening velocity. Isolated cells were elongated, Ca 2+ tolerant, and contracted rapidly and substantially when exposed to cholinergic agonists, KCl, serotonin, or caffeine. Adult cells were longer and wider than preterm cells. Mean cell length in 1.6 mM CaCl 2 was 194 ± 57 (SD) µm ( n = 66) for adult cells and 93 ± 32 µm ( n = 20) for preterm cells ( P