Effect of metabolic inhibition on sodium ion exchange in the ventral nerve cord of Melanoplus differentialis

Abstract

Radioisotopic studies with 22Na were conducted in vitro on nerve cords of the grasshopper Melanoplus differentialis. 2. The total uptake of 22Na by nerve cords is significantly decreased by the presence of 5 mM azide in the incubation medium. 3. Six components were extracted from desaturation curves of nerve cords, after which some residual radioactivity remained in the majority of cases. 4. The size of the third efflux component is decreased significantly and that of the fourth efflux component is increased significantly by metabolic inhibition during incubation. 5. It was concluded that the intact nerve cord of M. dzyeerentiulis actively absorbs Naf from the bathing medium.

Ultrastructural study of the neural fat-body system in the cockroach Periplaneta americana

“…If the site of active transport in the nervous system of P. americana is located in the granular layer of the neural fat body, as suggested for other species by Diecke (1970a), andWeidler et al (1974), then it also may be postulated that in Periplaneta the entire fat-body system (i.e., fat body and neural lamella) may be involved since the granular layer covering the fat-body cells is continuous with that of the neural lamella. The granular layer of the neural lamella is present, and may provide active transport, in areas where there are no fat-body cells.…”