BRAIN TEMPERATURE AND THE NEUROPROTECTIVE ACTION OF ENADOLINE AND DIZOCILPINE IN THE GERBIL MODEL OF GLOBAL-ISCHEMIA

Mongolian gerbils were subjected to transient forebrain ischaemia by o ccluding both common carotid arteries for 7 min. Subcutaneous administ ration of either the kappa-opioid receptor agonist enadoline (CI-977; 1 mg kg-1), or the non-competitive NMDA receptor antagonist dizocilpin e (MK-801; 3 mg kg-1), at induction of ischaemia prevented neurodegene ration of CA1-CA2 pyramidal neurones in the dorsal hippocampus. It was shown by continuously monitoring intrahippocampal temperature that br ain temperature drops by approximately 4-degrees-C during ischaemia, w hen rectal temperature is maintained normothermic. Enadoline at no tim e point tested affected brain temperature, whereas dizocilpine statist ically lowered brain temperature following ischaemia. These findings s uggest that enadoline affords neuroprotection in the absence of any hy pothermic episode, whilst in the case of dizocilpine, the small transi ent hypothermia observed following ischaemia may act synergistically o r additively with the drug to yield neuroprotection.