Busca avançada
Ano de início
Entree
(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Calcium transport in gill cells of Ucides cordatus, a mangrove crab living in variable salinity environments

Texto completo
Autor(es):
Leite, V. P. [1] ; Zanotto, F. P. [2]
Número total de Autores: 2
Afiliação do(s) autor(es):
[1] Univ Fed Sao Paulo UNIFESP, Dept Renal Physiol, Sao Paulo - Brazil
[2] Univ Sao Paulo, Inst Biociencias, Dept Physiol, BR-05508900 Sao Paulo - Brazil
Número total de Afiliações: 2
Tipo de documento: Artigo Científico
Fonte: COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY; v. 166, n. 2, p. 370-374, OCT 2013.
Citações Web of Science: 6
Resumo

Crustaceans show discontinuous growth and have been used as a model system for studying cellular mechanisms of calcium transport, which is the main mineral found in their exoskeleton. Ucides cordatus, a mangrove crab, is naturally exposed to fluctuations in calcium and salinity. To study calcium transport in this species during isosmotic conditions, dissociated gill cells were marked with fluo-3 and intracellular Ca2+ change was followed by adding extracellular Ca2+ as CaCl2 (0, 0.1, 0.25, 0.50, 1.0 and 5 mM), together with different inhibitors. For control gill cells, Ca2+ transport followed Michaelis-Menten kinetics with V-max = 0.137 +/- 0.001 Delta Ca(2+)i (mu M x 22.10(4) cells(-1) x 180 s(-1); N = 4; r(2) = 0.99); K-m = 0.989 +/- 0.027 mM. The use of different inhibitors for gill cells showed that amiloride (Na+/Ca2+ exchange inhibitor) inhibited 80% of Ca2+ transport in gill cells (V-max). KB-R, an inhibitor of Ca influx in vertebrates, similarly caused a decrease in Ca2+ transport and verapamil (Ca2+ channel inhibitor) had no effect on Ca2+ transport, while nifedipine (another Ca2+ channel inhibitor) caused a 20% decrease in Ca2+ affinity compared to control values. Ouabain, on the other hand, caused no change in Ca2+ transport while vanadate increased the concentration of intracellular calcium through inhibition of Ca2+ efflux probably through the plasma membrane Ca2+-ATPase. Results show that transport kinetics for Ca2+ in these crabs under isosmotic conditions is lower compared to a hyper-regulator freshwater crab Dilocarcinus pagei studied earlier using fluorescent Ca2+ probes. These kinds of studies will help understanding the comparative mechanisms underlying the evolution of Ca transport in crabs living in different environments. (C) 2013 Elsevier Inc. All rights reserved. (AU)

Processo FAPESP: 09/15546-3 - Caracterização do transporte de cádmio em interação com o cálcio em células epiteliais de Ucides cordatus, um caranguejo de mangue
Beneficiário:Flavia Pinheiro Zanotto
Modalidade de apoio: Auxílio à Pesquisa - Regular