Acetylcholinesterase and anti-glycoprotein IIb staining of megakaryocytes in the spleens of female mice. Megakaryocytes in a heterozygous mutant spleen (C and D) were positive for acetylcholinesterase staining. The appearance of the positive staining cells is morphologically similar to megakaryocytes in a wild-type spleen (A and B). Note that there are more megakaryocytes in the mutant mouse spleen. These cells were also positive for glycoprotein IIb (E and F). Original magnifications × 20 (A, C, and E) and × 80 (B, D, and F).