Acetylcholine and Choline Contents of Rat Skeletal Muscle Determined by a Radioenzymatic Microassay: Effects of Drugs
Skeletal muscle contains a small amount of acetylcholine (ACh) relegated primarily to the nerve terminals in the endplate region (10), and a large quantity of choline (3). The ratio of the concentrations of choline:ACh in muscle is at least two orders of magnitude greater than it is in brain. Due to these particular characteristics some of the recently devised radio-chemical and chemical methods are unsuitable for the determination of ACh in this tissue since they lack either sufficient sensitivity or the necessary capacity to separate quantitatively the ACh from the high choline. Gas chromatography-mass fragmentography methodology (5, 11) has the required sensitivity and separative capacity, and is currently used for muscle ACh assay. Mass fragmentography is, however, expensive and not available to everybody. Hence, the relative dearth of information on drug effects on muscle ACh content, although such studies are warranted to complement extensive knowledge on drugs affecting the neuromuscular junction, obtained by physiological and electrophysiological means.
KeywordsExtensor Digitorum Longus Extensor Digitorum Longus Muscle Buffer Substrate Acetylation Reaction Choline Content
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