In vitro effects of prolactin, cortisol, aldosterone, and cyclic amp on branchial Na+, K+ - activated ATPase of the killifish, Fundulus heteroclitus
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چکیده
!!! vitro effects of prolactin, cortisol, aldosterone, and cyclic ad.enosine monophosphate were studied on branchial Na+, K+ activated ATPase of freshwater adapted killifish, Fundulus heteroclitus. Decreases in ATPase activity were found after treatment with prolactin and aldosterone. Cyclic AMP caused an increase in ATPase activity. The action of cortisol on this enzyme was not clear. A dose response xelationship was found only for cyclic AMP. It is proposed that cyclic AMP may be involved in the adaptation of£:.• heteroclitus to seawater.
منابع مشابه
Na+-dependent Ca2+ uptake in isolated opercular epithelium of Fundulus heteroditus
It is concluded that Ca2+ transport across the basolateral membranes of the ionocytes in killifish skin is mediated for the major part by a Na+/Ca2+-exchange mechanism that is driven by the (transmembrane) Na+ gradient established by N a+/K +-ATPase. The conclu sion is based, firstly, on the biochemical evidence for the presence of a Na+/Ca2+-exchanger next to the Ca2+ATPase in the basolateral...
متن کاملWe examined the involvement of mitochondria-rich (MR) cells in ion uptake through gill epithelia in freshwater-adapted killifish Fundulus heteroclitus, by morphological observation of MR cells and molecular identification of the vacuolar-type proton pump
narrow physiological range, equivalent to about one-third seawater osmolality. The gills, kidney and intestine are important osmoregulatory organs in fishes, creating ionic and osmotic gradients between the body fluid and external environments (Evans, 1993). It is well established that gill mitochondria-rich (MR) cells, or chloride cells, are responsible for salt secretion in seawater-adapted f...
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Maintenance of ion balance requires that ionoregulatory epithelia modulate ion flux in response to internal or environmental osmotic challenges. We have explored the basis of this functional plasticity in the gills of the euryhaline killifish Fundulus heteroclitus. The expression patterns of several genes encoding ion transport proteins were quantified after transfer from near-isosmotic brackis...
متن کاملFundulus heteroclitus acutely transferred from seawater to high salinity require few adjustments to intestinal transport associated with osmoregulation.
The common killifish, Fundulus heteroclitus, has historically been a favorite organism for the study of euryhalinity in teleost fish. Despite the species' large range of salinity tolerance, studies of osmoregulation in high salinity are rare, with most previous studies focused on fish transferred between freshwater and seawater. Similarly, while branchial transport properties have been studied ...
متن کاملDDT inhibition of (Na+, K+)-activated ATPase in gill tissue of Fundulus heteroclitus
The DDT i nh ibition of (Na+, K+) a ctivated ATPase in gill pre parations of the euryhaline teleost , Fundulus heteroclitus, was measured. The (Na+, K+) -activate d ATPase was found to be sensitive to DDT, with 74.6% of the e nzyme's specific activity inhibited by 20 ppm DDT . The (Mg++)-activated ATPase was also sensitive to inhibition bv DDT but not to the extent of the (Na+, K+) activat ed A...
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