Endothelin-mediated cell signaling and proliferation in cultured rabbit corneal epithelial cells.

摘要: PURPOSE To determine if there is endothelin-mediated regulation of cell signaling and proliferation in rabbit corneal epithelium. METHODS Endothelin-1 (ET-1) gene protein expression by the epithelial (RCE) cells were analyzed polymerase chain reaction, sequence analysis, enzyme immunoassay. DNA synthesis was characterized [3H]-thymidine uptake. Endothelin receptor linkage to pathways determined based on measurements dose dependent effects ET-1, ET-2, ET-3 intracellular Ca2+ concentration ([Ca2+]i) transients fura-2-loaded cells, ET-1 phosphoinositide turnover cAMP accumulation isolated RESULTS The authors detected mRNA for prepro RCE ET-like immunoreactivity identified conditioned culture medium. (1 nM) maximally stimulated uptake twofold (EC50 = 0.3 nM). Endothelins elicited transient increases [Ca2+]i with a rank order potency > or ET-2 >> ET-3. These consisted both mobilization influx from bathing solution. Intracellular linked IP3 because 1 microM increased content 48% its control value 23 nM), whereas occurred through non-L-type channel preexposure nicardipine did not affect either height duration transient. One micromolar required elicit significant increase 69% value. This presence solution comparable nonadditive that ionophore, A23187 microM). CONCLUSION data suggest endothelin production primary cultures can mediate an ETA subtype. subtype appears be involved ETs transients, turnover, accumulation.