Sea urchin effect

Acanthaster sea urchins, effect on humans, 316 2-Acetyl-9-azabicyclo[4.2. IJnonene, structure, 108,105/... 

Representative nickel-sensitive aquatic species show sublethal effects at 11.7 to 125 pg Ni/L. These effects include altered immunoregulatory mechanisms in tissues of the rainbow trout at 11.7 pg/L (Bowser etal. 1994), inhibited reproduction of daphnids at 30 pg/L, growth inhibition of freshwater and marine algae at 30 to 125 pg/L, reduced growth of rainbow trout at 35 pg/L, accumulation from the medium by mussels at 56 pg/L, and abnormal development of sea urchin embryos at 58 pg/L (NRCC 1981 WHO 1991 Outridge and Scheuhammer 1993 Table 6.7). 

Nakamura, S., C. Ohmi, and M.K. Kojima. 1989. Effect of zinc ion on formation of the fertilization membrane in sea urchin eggs. Zool. Sci. (Japan) 6 329-333. 

Ozretic, B. and M. Krajnovic-Ozretic. 1985. Morphological and biochemical evidence of the toxic effect of pentachlorophenol on the developing embryos of the sea urchin. Aquat. Toxicol. 7 255-263. 

The inhibition of amino-acid transport has been regarded as the main toxic effect of mercury compounds [82], The biochemical mechanism underlying the inhibition is unclear. In unfertilized sea-urchin eggs an interaction with the amino-acid carrier was found, whereas in fertilized eggs inhibition of amino-acid transport was indirect and might result from an elevation of the Na + content of the egg caused by the inhibition of the Na+ pump [83]. The action on the diffusional process could be mediated by an effect on membrane phospholipids or on membrane proteins, or by interaction with Ca2+ which stabilizes membrane structure. Mercuric chloride in skate liver cells inhibited amino acid transport, decreased Na + /K + -ATPase (adenosinetriphosphatase) activity, impaired volume regulatory mechanisms and increased the permeability of the plasma membrane to potassium [84]. It has been suggested that... 

Schnitzler I, Boland W, Hay ME (1998) Organic sulfur compounds from Dictyopteris spp. deter feeding by an herbivorous amphipod (Ampithoe longimana) but not by a herbivorous sea urchin (Arbaciapimctulata). J Chem Ecol 24 1715-1732 Shen Y, T sai PI, Fenical W, Hay ME (1993) Secondary metabolite chemistry of the Caribbean marine alga Sporochnus bolleanus. a basis for herbivore chemical defense. Phytochemistry 32 71-75 Schupp PJ, Paul VJ (1994) Calcium carbonate and secondary metabolites in tropical seaweeds variable effects on herbivorous fishes. Ecology 75 1172-1185 Smit AJ (2004) Medicinal and pharmaceutical uses of seaweed natural products a review. J Appl Phycol 16 245-262... 

White SJ, Jacobs RS (1983) Effect of stypoldione on cell-cycle progression, DNA and protein-synthesis, and cell-division in cultured sea urchin embryos. Mol Pharmacol 24 500-508... 

An interesting effect of Ca2+ ions on the autoxidation of hydroxy-1,4-naphthoquinone, which may have a bactericidal function in sea urchins, has been reported. Autoxidation resulted in the detection of a semiquinone, which was accompanied by only minimal oxygen uptake. The presence of Ca2+ resulted in a massive enhancement in the rate of 02 uptake. Potentiometric titrations revealed that Ca2+ ions, by forming complexes with the compound, lowered the pKa values of its phenolic groups, thereby generating the oxidation-prone phenolate anions. Autoxidation was also facilitated by the spin stabilisation effect of the Ca2+ ions on the naphthosemiquinone.121 This effect may be of importance in mammalian cells, where quinones induce elevations in the free Ca2+ concentration. 

The proportion of sulfolipids in the gonads of sea urchins changes during early development of the embryos.283 It has also been found that the sulfolipid from P. depressus exerts a stimulating effect on the respiration of the spermatozoa of the sea urchin.308... 

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