Spinothalamic projections in amphibians as revealed with anterograde tracing techniques

Direct spinothalamic pathways were demonstrated in anurans (Rana ridibunda, Xenopus laevis) and in the ribbed newt, Pleurodeles waltl. With the powerful anterograde tracers Phaseolus vulgaris leucoagglutinin and biotinylated dextran amine, rather extensive spinothalamic projections were found, including the ventromedial thalamic nucleus, the dorsal thalamus and several posterior diencephalic nuclei (anurans), and the neuropil lateral to the pars ventralis thalami as well as to the anteroventral and posterodorsal zones (P. waltl), respectively.