Qualitative X-ray spectrometric study to demonstrate ruthenium in central nervous system structures, after intraperitoneal injection of ruthenium red to adult rats.

A qualitative X-ray spectrometric study oriented to demonstrate ruthenium (Ru) in central nervous system was made after intraperitoneal (i.p.) injection of ruthenium red (RuR) to adult rats. Ru signals were depicted in the brain synaptosomal fraction since 60 min after RuR i.p. administration, corresponding to the latency period of the convulsive model injecting RuR systemically to adult rats. Ru signals were initially detected in pineal gland and periventricular regions, whereas X-rays from Ru atoms in cerebral cortex were detected at longer time intervals after RuR i.p. injection. It is concluded that RuR, a non-liposoluble substance, when injected systemically, passes from the blood stream to brain parenchyma, probably through areas without blood-brain barrier, reaching the neural elements related to the mechanisms of production of convulsions.