In vivo, EMG responses were similarly quantified in a 4–8 ms window after the last stimulus (Figure 6B). To test grip strength, adult mice were placed on a cage top. The cage top was lightly shaken to encourage selleck chemicals llc gripping of the horizontal bars. The cage top was slowly inverted and positioned at least thirty centimeters above the landing surface. The latency to fall was measured. Each mouse underwent this test three times in a single day. With some mice, we repeated the test three times on a separate day. The results did not vary in the additional trials. The average weight of the dI3OFF mice
(16.0 ± 3.7 g, n = 5) was not significantly greater than that of the control littermates (16.0 ± 2.6 g, n = 7). To test for the presence of a forepaw grasp reflex in neonates (P1–P7), we gently stroked the palmar surface of the forepaw with a glass capillary and observed any flexion of the fingers. This test was performed without prior knowledge of the genotype of the pups. Additional behavioral analyses are described in Supplemental Information. Unless otherwise noted, data are reported as mean ± SD, and comparisons were performed using a Student’s unpaired t test with unequal variance and a threshold for significance set at 0.05. We thank Angelita Alcos, Bithika Ray,
Apiraami Thana, and Nadia Farbstein for excellent technical Selleckchem AZD2281 assistance; Joshua Sanes and Silvia Arber for the generous contribution of mouse strains; Natalie Parks and Dan Marsh for assistance with chronic spinalization; Jason Meissner and Allison Reid for aid with the von Frey test; Anatoliy Voskresenskiy and Leigh Sadler for work with the horizontal ladder experiments; Jonathan Carp and Jonathan Wolpaw for their suggestions in designing
the nerve cuff electrodes; Patrick Whelan and Meggie Reardon for help with the isolated spinal cord preparation with sural nerve in continuity; Frédéric Bretzner, Pratip Mitra, Philippe of Magown, Izabela Panek, and Sabrina Tazerart for discussions; and Kevin Bourke for photography. We also thank patient D.F., whose disabling grasp reflex led to a portion of the work described. T.V.B. was supported by a Nova Scotia Health Research Foundation fellowship and a Canadian Institutes of Health Research (CIHR) Fellowship. T.M.J. is an investigator of the Howard Hughes Medical Institute and was supported by the National Institutes of Health (R01-NS033245), Project A.L.S., and the Harold and Leila Mathers Foundation. This research was funded by a grant to R.M.B. from the CIHR (FRN 79413) and was undertaken thanks, in part, to funding to R.M.B. from the Canada Research Chairs program. “
“(Neuron 77, 696–711; February 20, 2013) Measurements of action potential duration in Figures 1, 3, 5G, 6D, and S1 display an apparent three-point periodicity. We clarify that this effect results from using 60 Hz stimulus trains that have fractional 16.67 ms interstimulus intervals (ISIs).