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Paraventricular nucleus (PVN) neurons that project to the spinal cord are important in the control of sympathetic outflow. Angiotensin II (Ang II) can stimulate PVN neurons, but its cellular mechanisms are not clear. In this study, we determined the effect of Ang II on the excitatory and inhibitory synaptic inputs to spinally projecting PVN neurons. Whole-cell patch-clamp recordings were performed on PVN neurons labeled by a retrograde fluorescence tracer injected into the thoracic spinal cord of rats. Immunocytochemistry labeling revealed that the immunoreactivity of angiotensin type 1 (AT₁) receptors was colocalized with a presynaptic marker, synaptophysin, in the PVN. Application of 0.1–5 μm Ang II significantly decreased the amplitude of evoked GABAergic IPSCs in a concentration-dependent manner. Also, Ang II decreased the frequency of miniature IPSCs from 2.56 ± 0.45 to 1.05 ± 0.20 Hz (p < 0.05; n …