Figure 6. TRPM8 Is Necessary for the Increase in Motor Neuron Number and the Adaptation of the Sensorimotor Response of Animals Grown in Cold Temperatures.

(A) Images show cross-sections of immunostained spinal cord (outlined) for HB9 from Control-MO- or TRPM8-sbMO-containing stage 40 larvae grown in cold temperature (16°C). Scale bar, 20 μm.

(B) Graph shows number of HB9-immunopositive cells per 100 μm of spinal cord; mean ± SEM from at least 220 μm-length spinal cord per larva, n = 5 larvae per condition, **p < 0.005, two-tailed t test.

(C-G) TRPM8-sbMO or Control-MO stage 37/38 (C) and 40 (D–G) larvae grown in cold temperature (16°C) were subjected to 20 trials each of gentle touch at cold (14.5°C) or warm (22.5°C) temperature. Responses were video recorded at 30 Hz, n = 6 larvae per condition.

(C) Average percentage of incidence of each response.

(D) Time course of changes in speed during initial phase (first 200 ms) of the swim response.

(E) Swim duration.

(F) Maximum speed during initial phase of the swim response.

(G) Maximum tangential acceleration during initial phase of the swim response.

In (D)–(G), data are mean ± SEM. In (C) and (E)–(G), the letters on top of datasets indicate significant (different letters) or not significant (same letters) differences, p < 0.05, 2-way ANOVA, Tukey post hoc test.

See also Video S5.