EFFECTS OF LINDANE EXPOSURE ON RAINBOW-TROUT (ONCORHYNCHUS-MYKISS) IMMUNITY .3. EFFECT ON NONSPECIFIC IMMUNITY AND B-LYMPHOCYTE FUNCTIONS

The effect of the organochlorine insecticide lindane (gamma-hexachlorocyclohexane) was examined on some major immune functions of rainbow trout (Oncorhynchus mykiss) on the chemiluminescent response of pronephric cells (PMA-induced) in phagocytosis, on the proliferation of lymphocytes with B and T mitogens, and on the number of B lymphocytes analyzed by cytofluorometry. Two different methods of exposure were tried via food (first protocol) and via a single intraperitoneal injection (second protocol). After the oral contamination at a daily body dose of 1 mg/kg for 30 days, a decreased chemiluminescent response was observed which persisted for two more weeks and disappeared over 1.5 months. No effect was observed on lymphocyte proliferation and on the number of circulating B lymphocytes. In the second protocol lindane was administered intraperitoneally at 10, 50, or 100 mg/kg body wt. After 45 days the lymphocyte proliferation of B cells was depressed but not the T cell one. The B cells number in head kidney as measured by cytofluorometry was not significantly modified. Some nonspecific immunity parameters in sera were significantly modified. (C) 1994 Academic Press, Inc.