Purkinje Fiber


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Purkinje Fiber

 

a cellular element found in the conduction system of ventricular myocardium; described in 1845 by J. E. Purkinje. Purkinje fibers are particularly large in ruminants. They have been studied mainly in mammals but appear to exist in other vertebrates as well. Although they are of muscular origin, Purkinje fibers have largely lost their contractile function and have become specialized in the conduction of excitation to contractile elements of the myocardium; this accounts for their meager number of myofibrils. Purkinje fibers are usually thicker than the contractile fibers of the myocardium and are rich in mitochondria and glycogen.

References in periodicals archive ?
Neurons from the contralateral vestibular nuclei and Purkinje fibers from the cerebellum are believed to exert their inhibitory effects via this GABAergic system.
The electrical impulses split here into the right and left bundles that travel through each side of the ventricles and wind up in the Purkinje Fibers which cause the ventricle to contract.