Prostaglandin F synthase, producing prostaglandin F(2 alpha) and 9 alpha,11 beta-prostaglandin F(2), has at least two isozymes, lung-type and liver-type ones. The present study including double immunolabelling with microtubule-associated protein 2 indicated that the lung-type isozyme was present in neuronal dendrites and somata of gray matter (relatively intense in lamina I and II in dorsal horn, and IX in ventral horn) and vascular endothelial cells in the rat spinal cord at all segmental levels.