D-penicillamine induced changes on rat mast cell cyclic GMP levels.

The cGMP accumulation in rat serosal mast cells was measured after cell treatment with D-penicillamine, a sulphydryl containing compound. Preincubating the cells with increasing doses of the drug causes a decrease of basal level of the nucleotide. In cells activated with the degranulating agent 48/80 there is a sharp increase in cGMP intracellular levels. D-Penicillamine prevents the nucleotide accumulation caused by compound 48/80, decreasing even the steady-state level in activated cells. The effect on cGMP metabolism does not correspond to an inhibition of histamine release.