Characteristics of scratching movements performed by control and knock-out mice. A–C, Representative examples of activity of the left and right Tib during scratching evoked by unilateral stimulation of the pinna in control (A), V0Glut-KO (B), and V0-KO (C) mice. Tib-ip, Tib ipsilateral to the stimulation site; Tib-co, Tib contralateral to the stimulation site. Note, that in control mice rhythmic activity was observed in Tib-ip only, while in both V0Glut-KO and V0-KO mice synchronous rhythmic bursts of activity in Tib-ip and Tib-co were generated. Red dashed lines demarcate the scratching cycles. D, Circular diagram showing the mean (±SD) value of the phase shift between movements of hindlimbs during scratching performed by V0Glut-KO (N = 4, n = 46) and V0-KO (N = 6, n = 76) mice. E, The mean frequency (±SD) of scratching in control (N = 6, n = 63), V0Glut-KO (N = 4, n = 63), and V0-KO (N = 7, n = 89) mice. F–I, The mean (±SD) values of the normalized to the body length amplitude of the limb protraction (F), and of the amplitude of the scratching movements in the dorsoventral (G), rostrocaudal (H), and mediolateral (I) directions in control and KO mice. Ip, hindlimb ipsilateral to stimulation site; Co, hindlimb contralateral to stimulation site. In F: control, N = 7, n = 11; ipsilateral limb of V0Glut-KO mice, N = 4, n = 15; contralateral limb of V0Glut-KO mice, N = 7, n = 15; ipsilateral limb of V0-KO mice, N = 8, n = 16; contralateral limb of V0-KO mice, N = 8, n = 16. In G: control, N = 5, n = 84; ipsilateral limb of V0Glut-KO mice, N = 4, n = 84; contralateral limb of V0Glut-KO mice, N = 3, n = 50; ipsilateral limb of V0-KO mice, N = 6, n = 273; contralateral limb of V0-KO mice, N = 6, n = 226. In H: control, N = 6, n = 108; ipsilateral limb of V0Glut-KO mice, N = 4, n = 98; contralateral limb of V0Glut-KO mice, N = 4, n = 98; ipsilateral limb of V0-KO mice, N = 6, n = 181; contralateral limb of V0-KO mice, N = 6, n = 181. In I: control, N = 6, n = 181; ipsilateral limb of V0Glut-KO mice, N = 4, n = 179; contralateral limb of V0Glut-KO mice, N = 4, n = 162; ipsilateral limb of V0-KO mice, N = 7, n = 288; contralateral limb of V0-KO mice, N = 7, n = 286. Indication of significance level: *p < 0.05; **p < 0.01; ***p < 0.001.