Effect of cytidine on the modification of phospholipid metabolism induced by ischemia.

[1-14C-]Arachidonic acid was injected into the lateral ventricle of the gerbils (meriones unguiculatus) two hours before producing brain ischemia by the bilateral ligation of the carotid arteries. Ten minutes before the carotid ligation a group of animals received an additional intraventricular injection of cold cytidine (2.5 mumol/brain). Control animals with and without cytidine, together with the ischemic group, were decapitated directly into liquid nitrogen ten minutes after carotid ligation or sham surgery. Cytidine is able to both stimulate arachidonic acid incorporation into lipids and noticeably correct the release of this acid from polar lipids induced by ischemia. Based on these findings, it is possible to assume that cytidine exerts an effect on the biosynthesis of phosphoglycerides as well as on their catabolic activities.