Inhibition of serotonin uptake by synaptosomes and glial cells induced by certain drugs

Uptake of [¹⁴C]serotonin by glial cells and synaptosomes in the rabbit cerebral cortex was studied. The value of K_m for serotonin uptake was the same (0.083±0.02 M) for both synaptosomes and glial cells. Cortical synaptosomes took up serotonin twice as fast as glial cells (the rates of uptake were compared as protein). Of the psychotropic drugs tested, the most active inhibitors of both synaptosomal and glial serotonin uptake were the tricyclic antidepressant imipramine and the psychostimulant cocaine which, in concentrations of 50 M, inhibited uptake of [¹⁴C]serotonin in synaptosomes by 90% and in glial cells by 75–80%.Laboratory of Neurochemical Pharmacology, Institute of Pharmacology, Academy of Medical Sciences of the USSR, Moscow. Department of Biochemistry, Tbilisi University. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 11, pp. 564–566, November, 1979.