Simplified technique for histochemical determination of three fiber types in equine skeletal muscle.
For determination of 3 muscle fiber types in equine skeletal muscle, a comparison of 2 preincubation buffers, each followed by myosin adenosine triphosphatase staining, was made. Serial sections of the muscle samples (n = 75) were preincubated in an acid buffer (pH 4.6) or a formaldehyde-glycine buffer (pH 7.25) and then were stained for myosin adenosine triphosphatase. Differentiation of muscle fibers into type I, IIA, and IIB was identical with both techniques; however, in the samples prepared at pH 4.6, type I fibers were black; type IIA, light gray; and type IIB, dark gray. In the samples prepared at pH 7.25, types I, IIA, and IIB fibers were white, light gray, and dark gray respectively. The formaldehyde-glycine preincubation buffer (at pH 7.25) gave more consistent results, was easier to prepare, and retained cytoarchitecture better, compared with the samples prepared at pH 4.6.
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D002021:Buffers; D005557:Formaldehyde; D005998:Glycine; D006651:Histocytochemistry / Q000379:methods; D006736:Horses / Q000033:anatomy & histology* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D009132:Muscles / Q000201:enzymology / Q000648:ultrastructure*; D009218:Myosins / Q000378:metabolism; D013194:Staining and Labeling / Q000379:methods
D002021:Buffers; D005557:Formaldehyde; D000251:Adenosine Triphosphatases; D009218:Myosins; D005998:Glycine