Calcitonin gene-related peptide in vitro stimulation of ciliary beat in human upper respiratory cilia.

Calcitonin gene-related peptide (CGRP) is one of the neuropeptides that is released in the human nasal mucosa after trigeminal nerve stimulation. We investigated the in vitro effect of CGRP on the ciliary beat frequency (CBF) of human upper respiratory cilia. Ciliated epithelium of freshly removed adenoidal tissues was used in all experiments. CBF was measured using a computerized photo-electric method. The results showed that CGRP exerted a significant dose-dependent stimulation on CBF in concentrations of 10(-9)-10(-6) M (n = 10), with a maximum of 23%. Our findings indicate that CGRP in vivo may help to protect the airway epithelium by directly stimulating ciliary beat.