“…The present findings are in general agreement with previous results, in so far as repeated administration of DMI or ECS has been shown to decrease presynaptic X2-adrenoceptor function (Tang et al, 1979;McMillen et al, 1980;Heal et al, 1981;1987a;Sugrue, 1983) and cortical f-adrenoceptor number (Bergstrom & Kellar, 1979a, b;Sellinger-Barnette et al, 1980;Asakura et al, 1982;Sugrue, 1982;1983;Stanford & Nutt, 1982;Stanford et al, 1983). Moreover, chronic ECS has previously been demonstrated to reduce cortical a2-adrenoceptors (Pilc & Vetulani, 1982;Stanford & Nutt, 1982;Heal et al, 1987a).…”