Figure 2.

Responses of gastro-esophageal vagal afferents to mechanical stimulation in mice deficient in mGluR4 (A*) or mGluR8 (B). (i) The effects of disrupting mGluR on the responses to circumferential tension (average impulses s⁻¹ over stimulus duration of 1 min) of tension receptors. (ii) The effects of disrupting mGluR on the responses to mucosal stroking (impulses per stroke, mean of eight strokes) of mucosal receptors. The graphs show the mean ± SEM. Significant differences between mGluR+/+ (•) and −/− (◦) mice (assessed using two-way ANOVA) is indicated adjacent to the response curves (*p < 0.05). n = number of afferents recorded. *Previously presented. The metabotropic glutamate receptor mGluR4 is required for normal visceral mechanotransduction (Page et al., 2004).