The action of juvenile hormone on follicle cells of Rhodnius prolixus in vitro: The effect of colchicine and cytochalasin B

Abstract

Juvenile hormone (JH) applied to vitellogenic follicles of Rhodnius prolixus in vitro causes the reversible development of spaces between the follicle cells. Colchicine at a concentration of 10 −2 to 10 −7 M inhibited this effect of JH in a dose-dependent manner, and there was a concomitant loss of organized microtubules as revealed by ultrastructural examination of the follicle cells. Cytochalasin B at 1, 5, 10 and 50 μg/ml also exhibited a dose-dependent and reversible inhibition of the JH effect. Cytochalasin B had no effect on follicle cell microtubules; at higher concentration (10 μg/ml), however, there was a loss of subplasmalemmal microfilaments. These results suggest that the maintenance of cytoskeletal integrity may be important in the action of JH on follicle cells at vitellogenesis.