Platelet adenylate cyclase activity was measured in 16 control subjects and 16 patients who developed post-traumatic stress disorder (PTSD) as a result of damage inflicted on their homes during the Iraqi Scud missile attacks on Israel which occurred during the 1991 Gulf War. There were no differences in basal, NaF-stimulated, PGE1-stimulated or forskolin-stimulated activity between controls and PTSD subjects. Epinephrine inhibition of forskolin-stimulated activity, an effect mediated by alpha 2 adrenergic receptors, was slightly but not significantly increased in the PTSD patients compared to the controls, while 5-HT induced inhibition, an effect mediated by putative 5-HT1a-like receptors, was unchanged. The relationship of these activities to measures of anxiety and depression in these patients is discussed.