COMPARISONS OF REPETITIVE-INSULT AND SINGLE-INSULT ISCHEMIA - EFFECTSON REGIONAL BRAIN-DAMAGE AND BEHAVIOR

SINGLE- and repetitive-insult ischaemia have been used with the gerbil to model human stroke and the impact of anti-ischaemic agents. It is currently not well-established whether the duration of an ischaemic in sult, or single vs repetitive insults may have different behavioural c onsequences. In this study, groups of gerbils were given either single - or repetitive-insult ischaemia of either 3, 6 or 9 min cumulative du ration. As the cumulative duration of ischaemia was increased, the deg ree of brain damage correspondingly increased and performance in a wat er maze task was progressively more impaired. However, no behavioural or brain-damage differences were found between groups of animals which received comparable durations of single- or repetitive-insult ischaem ia. Significant mortality was observed in the group receiving three 3 min ischaemic insults, suggesting that the repetitive ischaemia techni que may be limited to brief periods of occlusion. We conclude that the re are no grounds for distinguishing between the single- and repetitiv e-ischaemia paradigms when employing cumulative durations up to 9 min.