INVESTIGATIONS INTO THE PRODUCTION AND FUNCTION OF LEUKOTRIENES DURING HISTOTROPIC DEVELOPMENT OF OESOPHAGOSTOMUM-DENTATUM

The dynamics of production and excretion of leukotrienes by parasitic larvae of Oesophagostomum dentatum and their role for the development of the larvae were studied. Larvae were cultured in vitro to the fourt h stage (L4). Leukotriene B4 (LTB4) was detected in homogenates and in supernatant of larvae, with the homogenate-protein-based values stead ily decreasing during development. The homogenate-protein-based values of peptidyl leukotrienes (pepLT) remained fairly stable in both homog enates and supernatants, whereas the worm-count-based pepLT values inc reased significantly. The addition of diethylcarbamazine (DEC) to the culture medium straight from the beginning of culturing (12.8 or 25.5 mmol/l) reversibly hampered growth and development to L4. Application of DEC at 12.8 mmol/l beginning on day 13 of in vitro cultivation exer ted no significant effect on further development to L4. LTB4 appeared to counteract the inhibition of development by DEC. The results of thi s study indicate that endogenous LTs participate in regulation of the growth and development of O. dentantum.