Ciliary beat frequency in human respiratory explants.

Ciliary beat frequency was measured in 60 human bronchial explants obtained by bronchoscopic biopsy. The average rate of beating, at 37 degrees C, was 12.8 +/- 1.3 beats/s, and this rate remained quite constant for periods as long as 4 h. This basic rate of ciliary beat did not seem to be affected by factors such as age, topographical source of the biopsy, underlying disease, smoking history, or chronic alcohol consumption. The values obtained probably represented the "intrinsic" or automatic beat pattern. It remains to be seen if this pattern might be subject to modulation in situ.