title: Examination of chronically de-efferented cat muscle spindles for cholinesterase activity.
abstract: Cat tenuissmus muscles were deprived of motor nerve supply for three months by sectioning of the appropriate ventral spinal roots. Muscle spindles were located in the chronically de-efferented muscles and examined histochemically in serial transverse sections. Staining for nicotinamide adenine dinucleotide tetrazolium reductase showed that the spindle sensory innervation was preserved. The de-efferented intrafusal muscle fibers retained their differential staining with the reaction for myosin adenosine triphosphatase. However, all cholinesterase-active areas that are normally found along nuclear bag and nuclear chain intrafusal fibers demonstrated loss of the enzyme activity in the chronically de-efferented spindles. It is concluded that all histochemically demonstrable cholinesterase activity within the cat muscle spindle is dependent upon the continuous presence of motor innervation.
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D002415:Cats; D002802:Cholinesterases / Q000378:metabolism*; D004525:Efferent Pathways / Q000502:physiology; D006651:Histocytochemistry; D009046:Motor Neurons / Q000502:physiology; D009121:Muscle Denervation; D009132:Muscles / Q000032:analysis* / Q000166:cytology; D012584:Sciatic Nerve / Q000502:physiology
chemical_list: D000110:Acetylcholinesterase; D002802:Cholinesterases