Effect of catecholamines and corticosteroids on the cyclic nucleotide level in the splenic cells of immunized and nonimmunized rats

Red blood cells of sheep were shown to increase cAMP and cGMP levels in the rat spleen cells. The noradrenaline and adrenaline levels increased within first minutes after immunization in spleen tissue. Adrenalectomia counteracted the increase of cAMP and induced no change in the cGMP levels in spleen cells. HJydrocortisone (50 mg/kg) inhibited cyclic nucleotide responses to the sheep red blood cells.