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DYNAMICS FISH COMMUNITY IN THE AREA OF BREEDING AND FATTENING ESTUARY GUADALQUIVIR: PATTERNS OF DISTRIBUTION AND RECRUITMENT.Author: GARCIA GONZALEZ DIEGO. Year: 2004. University: CÓRDOBA [ www.uco.es]. Place of defense: FACULTAD DE CIENCIAS. Place of preparation: FACULTAD DE CIENCIAS. Summary: Between May 1997 and April 1999 samples using a boat angulero-camronero, the fish community of Lower Guadalquivir.Realizando nuestreos monthly cinso stations in the last 50 kilometers of estuary. Capturándose a total of 73 fish species belonging to 95 families. It has been found as species richness and abundance total community is increased gradually from the top to the mouth, showing a positive correlation with the salinity of the water. The species most representativs of the fish community are: E. Encrasicholus, S.pilchardus, P.minutus, D.punctatus, L. Saliens, L. Ramada, C.carpio, G. Holbrooki and a. Anguilla. They presented different penetration levels in the estuary closely with the salt gradient. Salinity and temperature of the water condition the space structure of the fish community. The health affects to a greater extent on the spatial structure of the community, while the temperature does on the temporal changes of the same. The community looks fish is the result of a series of actions anthropic (construction of dams, loss of hábitas, over-fishing, pollution) and is therefore very likely that the structure far from the com could be called "natural". Despite all these changes, the areas polihalina and mesohalina estuary (last 30 km) continuán acting as a breeding area for marine species. In fact, the large number of juveniles of marine species seasonal, which falls every year in the estuary, makes this category ecological have an important role in structuring their aquatic communities.
INSIGHT INTO THE EVOLUTION OF ANAPHYLATOXIN RECEPTORS THROUGH THE STUDY OF C3A AND C5A RECEPTORS IN RAINBOW TROUT (ONCORHYNCHUS MYKISS)Summary: Activation of the complement system results in the generation of anaphylatoxins C3a, C4a and C5a. In mammals, it has been shown that C3a and C5a elicit biological responses through their interactions with C3 and C5 receptors respectively. Although both receptors share a high degree of homology, until recently, very little was understood about the evolution of these receptors. In particular, it was not known whether or not these receptors were represented by a single common ancestral molecule in lower vertebrates. Here, we present the clonning and functional characterization of bona fise C3aR and C5aR in rainbow trout. While both receptors share a high degree of homology with their mammalian counterparts, the secondary structure of C3aR is unique in its truncated second extracellular loop. Antibodies generated against C3aR inhibited trout C3a-mediated intracellular calcium mobilization in trout leukocytes. While recombinantly expressed C5a was able to induce chemotaxis in trout peripheral leukocytes, antibodies generated against C5aR were found to inhibit this activity. Both C3aR and C5aR are expressed primary on B-cells, and to a lesser extent, on granulocytes. Our resluts indicate that, although highly homologous, the divergence of these two molecules into distinct receptors occurred prior to the emergence of teleost fish.
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