[Changes in the level of cyclic nucleotides in brain tumors].

Cyclic 3-5-adenosine-monophosphate and 3-5-guanosinemonophosphate concentrations were studied in the bioptate of brain tumors, examined during neurosurgical operation and in normal brain tissues. The correlations between cyclic nucleotides in the tumors appeared to be significantly decreased in comparison to the intact tissue, being a characteristic signs for all types of tumors. There were significant fluctuations in the level of cyclic nucleotides both in the tumours and nontumorous brain tissues. There were no correlations found between the level of cyclic adenosine-monophosphate and cyclic guanosine-monophosphate on the one hand and the duration of the disease, localization of the tumor, degree of the brain oedema and the type of narcosis on the other.