Fig. 3.

A, Schematic representation of amplitudes of compound action potentials from small foot muscles of 3-month-old P0^+/+ and P0^−/−mice with and without the Wld^smutation on distal stimulation of sciatic nerves. Note that theWld^s mutation has no influence on amplitudes in P0^+/+ genotypes. Amplitudes are markedly reduced in the absence of P0 (P0^−/−), but reduction is less pronounced in the myelin mutants carrying the homozygousWld^s mutation. Amplitudes from P0^−/− mice heterozygous for theWld^s mutation show a slight trend toward higher values compared with P0^−/− single mutants. ***p < 0.0001 and *p< 0.05. n, Number of individuals of the respective genotype investigated. B, Original recordings of compound action potentials from small foot muscles of P0^+/+ and P0^−/− mice with and without the Wld^s mutation on distal stimulation of sciatic nerves. Note the compact shape of muscle response in P0^+/+ mice independent of theWld^s mutation. P0^−/− mice without theWld^s mutation show predominantly dispersed responses, as shown here for two examples with relatively low and high amplitudes. Responses from P0^−/−/C57BL/Wld^smice are usually more compact, as presented here for a typical case (lower recording). Note the different scales of time and amplitudes.CMAP, Compound muscle action potential;WT, wild type; hom, homozygous;het, heterozygous.