The effect of neuronal activity on the competitive elimination of neuromuscular junctions in tissue culture.

The number of functional contacts between neurones of explanted ciliary ganglia and cultured muscle cells of the chicken, was determined electrophysiologically. After one week in culture the average muscle cell in the vicinity of a ganglion appeared to have contact with 2.5 neurones.

Effects of innervation by ciliary ganglia on developing muscle in vitro.

Electrophysiological and pharmacological properties of neuromuscular junctions formed in tissue culture between chick ciliary ganglia and chick skeletal muscle cells have been studied. Functional neuromuscular junctions are formed already within 24 h. No functional acetylcholine (ACh) esterase is present at these end-plates.