[Effect of suloctidil on the reduced evoked potentials in brain slices in low glucose perfusate]

Effects of suloctidil [erythro-1-(4-isopropylthiophenyl)-2-n-octylaminopropanol] on reduced evoked potentials in low glucose perfusate were studied using guinea-pig prepyriform cortex in vitro. The amplitude of evoked potential to paired electrical stimulation of the olfactory tract in cerebral slices was consistently and reversibly suppressed by the perfusion with low glucose (3 mM)-Krebs-Ringer's solution. The amplitude reduction after 10 min exposure to the perfusate was fairly reproducible in the same preparation. The amplitude reduction was always accompanied with significant facilitation of "postactivation potentiation", estimated from the size of the first and second response to paired stimulation. Perfusion of brain slices with low glucose Krebs-Ringer's solution containing 10(-7)-10(-6) g/ml suloctidil for 10 min, however, effectively prevented the reduction of amplitude of evoked potentials to below 30-50% of the control value. The facilitation of postactivation potentiation under the low glucose condition was also suppressed by the drug. Dihydroergotoxin, 3 X 10(-6) g/ml, also showed a comparable effect as 10(-6) g/ml suloctidil. These data suggest that suloctidil possesses a brain energy economizing effect such as activation of oxygen, glucose uptake or production of high energy substance.