Nitric oxide synthase imunolabeling in the molluscan CNS and peripheral tissues

NOS immunoreactivity was assayed in CNS and peripheral tissues of the sea s lugs Pleurobranchaea californica, Tritonia diomedea and Aplysia californica using different antisera against mammalian nitric oxide synthase in Wester n blots. Polyclonal anti-nNOS labeled at 250, 185, 170, 155, 100, 75, and 6 5 kD in extracts of Pleurobranchaea CNS, salivary gland and esophagus but n ot of gills or muscle. The labeling pattern for Tritonia in bands at 250, 2 00, 120/110, 100, 69, 65, and 60 kD differed somewhat. Anti-nNOS labeling i n Aplysia was markedly different, with bands labeled only at 69 and 60 kD i n CNS extracts, and at 200, 190, 69 and 60 kD in salivary and esophagus ext racts. The wide variation in NOS immunoreactivity is consistent with specie s differences in tissue localization and biochemical properties of mollusca n NOS isoforms. (C) 1999 Academic Press.