Taurine neurons in rat hippocampal formation are relatively inert to cerebral ischemia.

Abstract

It is well-known that transient cerebral ischemia causes selective loss of neurons in the hippocampus, striatum and cortical layers (14,24). It has been suggested that the difference in nerve cell vulnerability to ischemic damage is probably due to differences in the nature of their transmitters (14,22,27). For instances, GABAergic neurons in the striatum are more susceptible to transient ischemia than the cholinergic neurons (7) and dopaminergic neurons are more sensitive to ischemic damage than the GABAergic neurons in the gerbil brain (26). Since taurine has been demonstrated to have protective effects on the photoreceptor in the cat (12) and on the light-induced disruption of isolated frog rod outer segments (23), we decided to investigate the influence of transient cerebral ischemia on the taurine neurons in rat hippocampus. Taurine neurons were identified immunocytochemically with antibodies against cysteine sulfinic acid decarboxylase, the rate-limiting enzyme of taurine biosynthesis. Cysteine sulfinic acid decarboxylase has previously been used as a specific marker for identification of taurine neurons in the retina (10,17–19), cerebellum (3,4) and hippocampus (10,26,28).