GASEOUS NITRIC-OXIDE STIMULATES GUANOSINE-3',5'-CYCLIC MONOPHOSPHATE (CGMP) FORMATION IN SPRUCE NEEDLES

The influence of externally applied gaseous nitric oxide (NO) on spruc e needles in relation to cGMP formation has been examined. Exposure of spruce needles (Picea abies) to gaseous nitric oxide leads to a stron g and rapid increase of the cGMP concentration. Depending on the base level of cGMP in the untreated needles, the concentration of cGMP in t he NO exposed needles increased up to four degrees of magnitude. The c ontent of adenosine-3',5'-cyclic monophosphate (cAMP) remained below t he detection limit of the HPLC-method used (10(-7) moll(-1)). Therefor e, it was not subject to further investigation.