Two questions were asked: Does naltrexone attenuate the behavioural depression (BD) in other models of limbic epilepsy besides amygdala kindling? Does intracerebroventricular (ICV) administration produce the same effects as subcutaneous injection, i.e., attenuation of the BD. Male wistar rats with bipolar electrodes implanted bilaterally in the dorsal hippocampus and a metal cannula in the lateral ventricle were kindled through 1 electrode and EEG recorded through the contralateral electrode. Subcutaneous (sc) and ICV naltrexone administration attenuated the BD of hippocampal kindled rats. These results further implicate the brain opioid system in the postictal phase of kindling and possibly epilepsy.