Discontinuity of sarcoplasmic reticulum in the mid-sarcomere region in flight muscle of dragonflies.
The sarcoplasmic reticulum organization of dragonfly flight muscles is analyzed, with particular reference to the doubling existing at H-band level. This doubling could be explained as a consequence of a regular discontinuity in the sarcoplasmic reticulum covering myofibrils. In each sarcomere, two sleeves of the sarcoplasmic reticulum seem to overlap forming a telescopic system which can slide outside each other during the lengthening and shortening movements of the fiber.
D000818:Animals; D007313:Insecta / Q000648:ultrastructure*; D008854:Microscopy, Electron; D008954:Models, Biological; D009119:Muscle Contraction; D009132:Muscles / Q000648:ultrastructure; D009210:Myofibrils / Q000648:ultrastructure; D012519:Sarcoplasmic Reticulum / Q000648:ultrastructure*