Effect of pyridoxine deficiency in young rats on high-affinity serotonin and dopamine receptors

Abstract

The high‐affinity bindings of [³H]‐5‐hydroxytryptamine to serotonin S‐l receptors, [ H]‐ketanserin to serotonin S‐2 receptors in the cerebral cortex, [³H]‐fluphenazine to dopamine D‐l receptors, and [³H]‐spiroperidol to dopamine D‐2 receptors in the corpus striatum were studied in pyridoxine‐deficient rats and compared to pyridoxine‐supplemented controls. There was a significant increase in the maximal binding (B_max) of serotonin S‐l and S‐2 receptors with a significant decrease in their binding affinities (K_d). However, there were no significant changes either in the maximal binding or binding affinity of striatal dopamine D‐1 and D‐2 receptors. Receptor sensitivity seems to correlate negatively with the corresponding neurotransmitter concentrations in the pyridoxine‐deficient rats.