Cholinesterases and Innervation of Skeletal Muscles

Häggqvist, G. Cholinesterases and innervation of skeletal muscles. This investigation is directed to the possibility of a relationship between the behaviour of “specific cholinesterase” (AcChE), “non‐specific butyrylcholinesterase” (BuChE), the two types of nerve endings known to occur in muscles and the number of phasic and tonic fibres in muscle nerves. It has been shown that muscles predominantly innervated by delicate tonic fibres have endings of a “grappe type” and stain heavier for BuChE. Muscles innervated principally by coarse fibres with endings of a “plaque type” stain for AcChE. Muscles innervated by mixed coarse and thin fibres possess both kinds of endings and show centres for AcChE as well as BuChE. It seems probable that the “en plaque” endings of the phasic fibres contain AcChE, whereas the “en grappe” endings of the tonic nerves, contain BuChE.