Autor: |
Fleming, Warren R., Nichols, James, Potts, W. T. W. |
Zdroj: |
The Journal of Experimental Biology; April 1974, Vol. 60 Issue: 2 p267-273, 7p |
Abstrakt: |
Transfer of Fundulus kansae from 80% sea water to a low-calcium water containing 0·4 mm/1 Ca2+ caused a sharp rise in sodium efflux and a change in the kinetic pattern of efflux. A transient drop in whole-body sodium levels occurred within 1·2 days after transfer. Both sodium and potassium levels were normal after 9 days exposure to low-calcium saline. Transfer into low-calcium sea water increased the rate of incorporation of radio-phosphorus into gill RNA. Actinomycin-D blocked the stimulation of sodium turnover after transfer into low-calcium sea water. It did not affect the whole-body sodium or potassium levels of long-term sea-water adapted animals. Actinomycin-D reduced the sodium efflux of short-term sea-water adapted animals regardless of the environmental calcium concentration. The antibiotic also upset the balance of sodium fluxes in those animals held in low-calcium sea water. It is suggested that in addition to the generalized effect of calcium on perme-ability to monovalent ions and water, calcium serves to inhibit some of the synthetic processes involved in regulating sodium metabolism, and also serves to stabilize the metabolic machinery already present. |
Databáze: |
Supplemental Index |
Externí odkaz: |
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