Abstract
Beat frequency of dog tracheal ciliated epithelium was measured using a profile projector and a photomultiplier. The preparation, treated with 50 μm/ml of saponin for 15 min, lost osmotic behavior and ciliary beat came to depend on externally applied Mg ATP 2− indicating that ciliated epithelium is skinned with saponin. Beat frequency of skinned cilia did not increase with Ca 2+ in 0.1 mM Mg ATP 2− with not ATP-regenerating system. Under 4 mN Mg ATP 2− the beat frequency increased with an increase in Ca 2+ from 0.3 to 10 μM, although a marked beat continued in the virtual absence of Ca 2+. Both Ca 2+ sensitivity and maximum beat frequency increased with the addition of 2.4 μM calmodulin. The effect of calmodulin inhibitor (W-7) on skinned preparations was somewhat weaker than that on intact ones. We conclude that Ca 2+, within the physiological range of concentrations, directly activated the ciliary proteins and increased the ciliary beat frequency. The addition of calmodulin augments the effect of Ca 2+ but the basal beat frequency is not Ca 2+ dependent.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
