Figure 3. Effects of ibotenic acid (IA) microinjection into the vestibular subnuclei on the cardiorespiratory responses evoked by local electrical stimulation of VN_M (A), VN_L (B) and VN_S (C).

In each panel, the traces from the top to bottom are ABP, V_T, airflow and P_tr. The thin and thick bars indicate stimulation at 100 and 200 Hz, respectively. Group data comparing cardiorespiratory responses before and after local IA injection are depicted in D. The number of rats used for stimulation of the VN_M, VN_L and VN_S was six, two and two, respectively; the data are presented as means ±s.e.m.; *P < 0.05 between the responses to vestibular nucleus (VN) stimulation and control (without electrical stimulation); †P < 0.05 between the responses before and after IA injection. Please note that the MABP data were collected from six rats that exhibited a pressor response to VN_M stimulation at 150 Hz.