Fig. 3.

A: effect of injection of muscimol into sites dorsal to the caudal l/dlPAG on cardiovascular response to air jet stress (n = 4). Mean values for HR and MAP over time (min) after microinjection of VEH (100 nl; •) or MUS (300 pmol/100 nl; ○) into sites dorsal to caudal l/dlPAG at t= 5 min followed 5 min later by 20 min of air jet stress. Two-factor repeated-measures ANOVA [treatment and time as repeated factors) revealed no significant differences for interaction of treatment × time − HR: F (17, 51) = 0.89, P = 0.59; MAP: F (17, 51) = 1.31, P = 0.22]. B: schematic coronal sections of the rat brain adapted from the atlas of Paxinos and Watson (35) illustrating approximate sites of injections dorsal to caudal l/dlPAG in experiments for which data are reported at left. Numbers indicate distance from bregma in millimeters.