Effect of cyclic nucleotides on DNA synthesis in mouse lymphoid cells

The effect of eight cyclic purine and cyclic pyrimidine nucleotides on DNA synthesis on mouse lymphoid cells was investigated. Two out of eight compounds tested, namely 2', 3'-cyclic guanosine monophosphate (2', 3'-cGMP) as well as 3', 5'-cyclic guanosine monophosphate (3', 5'-cGMP), stimulate thymidine incorporation in all types of lymphocytes tested. The stimulatory activity of the cyclic guanosine nucleotides as well as the effects of lectins could be antagonized by 3', 5'-cyclic adenosine monophosphate (3', 5'-cAMP). 2', 3'-cGMP seems to stimulate preferentially mature T-cells while 3', 5'-cGMP preferentially acts on B-cells.