Ionizing irradiation affect extracellular nucleotide hydrolysis in brain of rats in different stages of development: i 15-day-old rats

Ionizing radiation affects plasma membrane functions mediated through transmembrane proteins including enzymes. Plasma membrane surface-located enzyme chain of ecto-nucleotide triphospho diphosphohydrolases (NTPDases) are involved in termination of cell purinergic signalization by hydrolysing extracellular adenosine tri- and di-phosphate (ATP and ADP). In the present study, effects of low (50 cGy) and therapeutic (2 Gy) dose of ionizing γ-irradiation on NTPDase activity in early postnatal rat brain neuronal cells were studied. Both low- and therapeutic doses significantly decreased hydrolyze of extracellular ATP (by 11% and 30%) and ADP (18% and 46%) in postnatal rats. These findings indicate that gammaradiation inhibits the enzyme activity in dose-dependent manner. This decreasing NTPDase activity 24h after whole body irradiation may lead to neuronal cell function disturbance, even cell death.Physical chemistry 2008 : 9th international conference on fundamental and applied aspects of physical chemistry; Belgrade (Serbia); 24-28 September 200