Studies on some central neurotransmitters in experimental uremia

ABSTRACT

Changes in some brain neurotransmitters and peptides in the thalamo- hypothalamic region of the brain of uremic rats were studied. Experimental uremia was induced in rats by bilateral ureteral ligation. Samples of blood were taken for the determination of non- protein nitrogen [NPN]. The activity of acetylcholinesterase as well as the concentrations of serotonin, insulin and adrenocorticotrophic hormones were determined in homogenates of the thalamo- hypothalamic regions of the brains of control and uremic rats. The mean level of plasma NPN was highly increased in uremic rats than in controls, denoting the occurrence of uremia. A significant decrease in acetylcholinesterase activity, whereas a dramatic decrease in the concentration of serotonin were found in homogenates of the thalamo- hypothalamic regions of brain of uremic rats compared with those of controls. Attempts were made to measure the concentration of the thalamo-hypothalamic insulin, but it was below the detectable level of the method used. A marked decrease in the concentrations of adrenocorticotrophic hormone [ACTH] was observed in the brains of uremic rats compared with those of controls. The present study suggested that many of the neurobehavioral changes in uremia might be due to metabolic disorders of some neurotransmitters and brain peptides