抄録
Domoic acid (DA) is the structural analogs of Kainic acid (KA) belongs to a group of amino acid analogues called excitotoxins. DA is shown to be about 10 times more toxic than KA. In rodents, DA produces extensive neuronal damage in the hippocampal pyramidal neurons and behavioral effects ranging from inactivity to seizures and distinguishable by its unique ability to elicit a scratching response. In the case of intraperitoneal DA administration, neuronal damage was observed in a wide range. In this study we examined the neuronal damage after intraperitoneal DA administration and cell proliferation in the adult rat whole brain. The most extensive neuronal cell damage was observed in CA3 subfield as evaluated by HE staining. While many TUNEL positive cells were observed in the granular cell layer of cerebellum. The process of neuronal cell death was made up mingled necrosis and apoptosis. TUNEL histochemistry revealed a time dependent sequential apoptotic cell death after DA administration. During the first 2 days postinjection, apoptosis in the cerebellum was only evident in the brain. At 3 days, the entire hippocampus and cortex become apoptotic. The distribution of the BrdU positive cells were most abundant in the dentate gyrus and not correlated to the degree of the neuronal damage. [J Physiol Sci. 2006;56 Suppl:S222]
