Cadaverine in the Rat Brain: Regional Distribution and Acylation of [14C]Cadaverine In Vivo and Uptake In Vitro

Abstract— The regional distribution and acylation of intraventricularly injected [¹⁴C]cadaverine was studied in the rat brain over a 48-h period. The concentrations of labeled cadaverine and its acyl derivatives, N -monoacetylcadaverine and N -monopropionylcadaverine, were determined in the telencephalon, striatum, hypothalamus, midbrain, cerebellum, and medulla-pons by TLC of their 5-dimethylamino-1-naphthalenesulfonyl derivatives, followed by liquid scintillation spectrometry. The apparent passage of radioactivity from the ventricular space into brain tissue was slow, with the concentrations reaching a peak at 24 h after injection. The percentage of radioactivity in the acyl forms of cadaverine, however, was maximal 4 h after injection, with the propionyl form predominating. The telencephalon, striatum, and hypothalamus contained the highest concentrations of radioactivity, in all three forms, at all elapsed times. A high-affinity uptake mechanism for cadaverine was demonstrated in slices of these tissues. This process was completely inhibited by equimolar concentrations of unlabeled putrescine.