Expression of acetylcholinesterase molecular forms during in vitro differentiation of rabbit embryonic muscle cells

We investigated the myogenic properties of rabbit myoblasts in culture, and examined particularly the expression of acetylcholinesterase (AChE). In the presence of horse serum, myoblasts proliferate quickly and begin to fuse by day 3 of culture. Differentiated myotubes presenting some spontaneous contractions are clearly visible from days 6 to 9. The cultures degenerate from day 10 onwards. The specific activity of AChE is low during the proliferation phase of myogenic cells, increases sharply as myotubes differentiated, then decreases as cultures degenerate. In 7-day-old cultures, globular forms are largely predominant and asymmetric forms, detected as A12, represent only 1% of the total activity.