| First Author | Leroy F | Year | 2014 |
| Journal | Elife | Volume | 3 |
| PubMed ID | 25313866 | Mgi Jnum | J:218031 |
| Mgi Id | MGI:5616469 | Doi | 10.7554/eLife.04046 |
| Citation | Leroy F, et al. (2014) Early intrinsic hyperexcitability does not contribute to motoneuron degeneration in amyotrophic lateral sclerosis. Elife 3:e04046 |
| abstractText | In amyotrophic lateral sclerosis (ALS) the large motoneurons that innervate the fast-contracting muscle fibers (F-type motoneurons) are vulnerable and degenerate in adulthood. In contrast, the small motoneurons that innervate the slow-contracting fibers (S-type motoneurons) are resistant and do not degenerate. Intrinsic hyperexcitability of F-type motoneurons during early postnatal development has long been hypothesized to contribute to neural degeneration in the adult. Here, we performed a critical test of this hypothesis by recording from identified F- and S-type motoneurons in the superoxide dismutase-1 mutant G93A (mSOD1), a mouse model of ALS at a neonatal age when early pathophysiological changes are observed. Contrary to the standard hypothesis, excitability of F-type motoneurons was unchanged in the mutant mice. Surprisingly, the S-type motoneurons of mSDO1 mice did display intrinsic hyperexcitability (lower rheobase, hyperpolarized spiking threshold). As S-type motoneurons are resistant in ALS, we conclude that early intrinsic hyperexcitability does not contribute to motoneuron degeneration. |
