|Aspecten van de osmo - en ionenregulatie van de fluwelen zwemkrab, Macropipus puber|
van Deijl, L. (1972). Aspecten van de osmo - en ionenregulatie van de fluwelen zwemkrab, Macropipus puber. NIOZ-rapport, 1972(15). Nederlands Instituut voor Onderzoek der Zee: Texel. 32, 17 pp.
Part of: NIOZ-rapport. Netherlands Institute for Sea Research (NIOZ): Den Burg. ISSN 0923-3210, more
The osmotic concentrations of blood and muscle extracts of the swimming crab Macropipus puber are compared with those in external medium using freezing point determination, after acclimation to different salinities. M. puber appeared able to tolerate salinities ranging from approx. 140°/oo to 43°/oo. Within this range the osmotic concentrations of blood and tissue follow external concentrations, so that this crab is an osmoconformer. The effect of temperature was studied following acclimation of the crabs to 5°C and 15°C. Apparently the tissue concentrations show stronger regulation at the higher temperature (15°C). The water content was determined by measuring the fresh and dry weight of muscle tissue. At 15°C it appeared independent of salinity, while at 5°C the water content increased with decreasing salinity. The contribution of electrolytes and organic compounds to the total osmotic concentration of these body fluids were determined using amongst others conductivity measurements. While these components account for approximately 2/3 of the tissue concentrations, the blood osmotic concentrations is largely due to electrolytes. 5. The time-course of adaptation of osmotic concentration muscles to a change in blood osmolarities, evidence an intracellular isosmotic regulatian. In order to determine in how far the measured tissue homogenate concentrations are representative of intracellular concentrations, inulin-injection experiments were performed, which indicate that homogenates include about 9.5% blood.