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Article: Myogenic heartbeat in the primitive crustacean Triops longicaudatus.
- Article from:
- The Biological Bulletin
- Article date:
- December 1, 1997
- Author:
CopyrightCOPYRIGHT 1997 Marine Biological Laboratory. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Introduction
The heartbeat of many crustaceans is neurogenic (reviewed by Krijgsman, 1952; Maynard, 1960; Prosser, 1973). The cardiac ganglion situated in the heart acts as a pacemaker. Neurogenic heart muscle has no endogenous rhythmical properties and is driven by periodic bursting activity of the cardiac ganglion via excitatory neuromuscular junctions. However, some diversity in the pacemaker mechanism of crustacean hearts has been reported recently. Yamagishi (1996) and Yamagishi and Hirose (1997) have shown, in the isopod Ligia exotica, that the heart of embryos and early juveniles exhibits myogenic heartbeats; i.e., the activity in the myocardium arises ...