Tension receptors associated with the tailspine muscles of the horseshoe crab,Limulus polyphemus

摘要: The distal portion of the flexor muscles powering tailspine movement in horseshoe crab is innervated by separate sensory and motor nerves. Records from nerve an undisturbed preparation show tonic afferent activity which increased tailspine. Splitting nerve, randomly isolated small bundles fibers, permitted identification individual units. Imposed lengthening or shortening passive muscle elicited unidirectional “movement” fibers. Another class units fired only upon active contraction showed with increasing length. These appear to be series tension receptors. Each receptor types observed phasic activity. Reflex could stimulation although identity afferents eliciting this was not determined. Methylene blue staining multipolar bipolar neurons near insertions, suggesting that these might receptors responsible for