| Popis: |
1. Effects of 2,2'-DCB on reproduction of the pond snail Lymnaea stagnalis have been studied with special emphasis on the neuroendocrine caudo-dorsal cells (CDCs). 2. Treated snails showed increased latencies of egg-laying after the clean-water stimulus needed for induction of egg-laying but not after injections with CDC-hormone containing extracts to induce ovulation, so the delay of oviposition originates before or during hormonal release from CDCs. 3. Electron microscopical observations of the commissures containing the axons of the CDCs showed a decreased number of exocytoses in treated snails. 4. In vitro effects of 2,2'-DCB treatment on the electrophysiology of the CDCs were also examined. 5. There was a slight effect on the resting membrane potential of the CDCs of treated snails, if the CDCs were divided into resting state CDCs (more negative than control resting state CDCs) and inhibited CDCs (less negative than control inhibited CDCs). During electrical activity of the cells, several treated snails showed CDC discharges with an unusual bursting pattern. 6. 2,2'-DCB treatment of snails affects reproduction. 2,2'-DCB or toxic metabolic intermediates may affect the endocrine function of the CDCs probably in combination with interference at the neuronal pathways involved in CDC activation. |
