[RNA-synthesizing activity of brain chromatin in rats with experimental alloxan diabetes]

Content of noradrenaline was decreased in neocortex and brain stem of rat brain by 70% and 50%, respectively, and that of serotonin--by 50% in the neocortex after development of the diabetic syndrome. At the same time, the RNA synthesizing ability of brain chromatin from the experimental animals was 3-fold higher as compared with controls. Catecholamines (L-DOPA, dopamine, noradrenaline) activated the RNA synthesis in controls by 40-50%, whereas in the animals with alloxane diabetes the effect was distinctly decreased. In vitro inhibitory effect of serotonin on the RNA synthesis was markedly decreased in preparations of brain chromatin from diabetic rats. Inhibitory effect of actinomycine D on the RNA synthesis was neutralized completely in controls after preincubation of the brain chromatin with L-DOPA, while only partial influence was detected in diabetic rats.