CHOLINESTERASE IN THE CRUSTACEAN MUSCLE RECEPTOR ORGAN

Localization and Properties of the Cholinesterase in Crustacean Muscle

Cholinesterase (ChE) activity is present in crustacean muscle extracts. However, since acetylcholine (ACh) is not a neuromuscular transmitter in these animals, the role and exact localization of ChE was unknown. The histochemical localization of the enzyme was studied in whole muscle and in the sarcoplasmic reticulum fraction of the extract, 50-microm frozen sections of glutaraldehyde-fixed cra...

Muscle fibres and efferent nerves in a crustacean receptor muscle

The accessory flexor muscle of the crab myochordotonal organ consists of two kinds of muscle-fibres. In one type the fibrillar material has a uniform punctate appearance in cross-section. The Z bands are often broken across the fibre width and are spaced 2 to 3/n apart. These resemble the 'Fibrillenstruktur' muscle of vertebrates. In the second fibre type the fibrillar material appears as large...

Intersegmental reflex actions from a joint sensory organ (CB) to a muscle receptor (MCO) in decapod crustacean limbs.

In the walking legs of decapod crustaceans, intersegmental reflex actions originate from various joint proprioceptors. The activity of the 'accessory flexor' (AF) muscle, which with the myochordotonal organ (MCO) constitutes a muscle proprioceptor for the mero-carpopodite (M-C) joint, is modulated by the sensory discharge of a joint receptor (CB chordotonal organ) for the more proximal, coxo-ba...

On the Excitation of Crustacean Muscle

IN the second paper of this series (Pantin, 1936) the responses of the muscles of various limbs to stimuli of different frequency and intensity in Carcinus maenas were described. Particular attention was paid to the flexor of the dactylopodite of the walking legs. If, while the frequency is kept constant, the intensity of the stimulus is gradually raised, the response of the muscle at first rem...

On the Excitation of Crustacean Muscle. I