Studies on the influence of adrenaline, acetylcholine and cysteine on suppressive activity of lymphocytes engaged in GvH reaction in rats.

Thirty-minute preincubation of lymphocytes deriving from popliteal lymph nodes of hybrid W X A F1 rats experiencing GvH reaction in 10(-6)M solution of acetylcholine resulted in an increased [3H]-thymidine incorporation both in cultures stimulated and nonstimulated with PHA. When the cells were preincubated for 30 min in 10(-5)M solution of adrenaline the level of [3H] TdR incorporation into non-stimulated cells was increased. The cells pretreated in such a way and added to cultures containing normal peripheral lymph node lymphocytes responding to PHA exhibited diminished or even abrogated suppressive effect which they normally exert if they are not treated with these two drugs. The PLN-cells preincubated in 2 mM solution of L-cysteine for 30 min, when added to the culture system showed an enhanced intensity of their suppressive effect.