“…When used in veterinary practice for the immobilization of animals larger doses are used, e.g. 7-48 ,Ag/kg, i.m., for the dog (Crooks, Whiteley, Jenkins & Blane, 1970). As a major aim in this study was a possible effect of etorphine on cortical synapses, the doses used in the rat were in the range of those producing catatonia (2 to 12 ,ug/kg, i.v.).…”