Alterations in muscles and motor endplates in the <i>Hgs</i>^<i>tn/tn</i> mice.

<p>(A) Wet weights of gastrocnemius muscles from 4 week-old <i>Hgs</i>^<i>+/+</i> and <i>Hgs</i>^<i>tn/tn</i> mice. (B) Ratio of gastrocnemius muscle weights to body mass. n > 6 mice per genotype for each time point. (C) Gastrocnemius muscle fiber size measurements for <i>Hgs</i>^<i>+/+</i> and <i>Hgs</i>^<i>tn/tn</i> mice. n > 6 mice per genotype. Symbols represent unpaired t-tests. (D) qPCR analysis of <i>AChR-α</i>, <i>AChR-β</i>, <i>AChR-δ</i>, <i>AChR-ε</i>, and <i>AChR-γ</i> mRNAs from the gastrocnemius muscles of 4-week-old <i>Hgs</i>^<i>+/+</i> and <i>Hgs</i>^<i>tn/tn</i> mice. n <b>></b> 3 mice per genotype. Symbols represent unpaired t-tests corrected for multiple comparisons using the Holm-Sidak method. (E) Motor endplate pathology in the <i>Hgs</i>^<i>tn/tn</i> mice. TA muscle fibers from <i>Hgs</i>^<i>+/+</i> and <i>Hgs</i>^<i>tn/tn</i> mice containing the <i>Thy1</i>-<i>Yfp</i> transgene (green) were stained with TRITC-α-bungarotoxin (red) to label the postsynaptic receptors. The presynaptic axons and nerve terminals are shown in green. Arrowheads mark ultra-terminal sprouting, and curved arrows mark swollen presynaptic terminals. Scale bar, 20 μm. (F) Quantitation of terminal swellings and terminal sprouting from <i>Hgs</i>^<i>+/+</i> and <i>Hgs</i>^<i>tn/tn</i> mice. n > 6 mice per genotype. Symbols represent unpaired t-tests corrected for multiple comparisons using the Holm-Sidak method. (G) Histogram of endplate area defined by TRITC-α-bungarotoxin (red) labeling of the postsynaptic AChR in <i>Hgs</i>^<i>+/+</i> and <i>Hgs</i>^<i>tn/tn</i> mice. An unpaired t-test with a Welch’s correction demonstrated a significant difference in the distribution of endplate size frequency between <i>Hgs</i>^+/+ and <i>Hgs</i>^tn/tn mice. n > 6 mice per genotype. Data are shown as mean ± SE. *p<0.05, **p<0.01 and ***p<0.001.