Role of calcium in the regulation of mechanical power in insect flight.

ABSTRACT: Most flying insect species use "asynchronous" indirect flight muscles (A-IFMs) that are specialized to generate high mechanical power at fast contraction frequencies. Unlike individual contractions of "synchronous" muscles, those of A-IFMs are not activated and deactivated in concert with neurogenically controlled cycling of myoplasmic [Ca(2+)] but rather are driven myogenically by oscillatory changes in length. The motor neurons of the A-IFMs, which fire at a rate much slower than contraction frequency, are thought to play the limited role of maintaining myoplasmic [Ca(2+)] above the critical threshold that maintains the muscle in a stretch-activatable state. Despite this asynchronous form of excitation-contraction coupling, animals can actively regulate power output as required for diffe

SUBMITTER: Gordon S 

PROVIDER: S-EPMC1449689 | biostudies-literature | 2006 Mar

REPOSITORIES: biostudies-literature