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Respuestas inmunológicas y cicatrización en el poliqueto Eurythoe complanata (Annelida: Amphinomidae) expuesto a cobre

Polychaetes exposed to 0.4 mg Cu +2 L –1 (2.14 mg CuSO4 5H2O L –1 ; 30% 96 h-LC50) for seven days and control individuals were divided into three groups: the first two were sensitized and non-sensitized with Micrococcus lysodeikticus, and the third was sensitized with heat-killed yeast. Lysozyme activity was tested in the first two groups and phagocytosis in the third one. Lysozyme was measured at 2 h and phagocytosis 15 min after immune sensitization. The effect of copper on wound healing was also examined in the polychaetes. For this, the polychaetes exposed and not exposed to copper were cut in two halves, and the body fragments were held in aquaria containing clean seawater, and the cicatrization was periodically observed. The lysozyme and phagocytosis responses were induced by the sensitization; however, these responses were inhibited after the metal exposure. On the other hand, 60–80% of the body fragments from the control group healed within four days, whereas the copper-treated individuals did not show cicatrization in the same period of time. In conclusion, the inhibition of the experimental activation of lysozyme and phagocytosis, and of wound healing in the polychaete Eurythoe complanata exposed to acute copper exposure, suggests the metal’s potential toxicity on the physiological mechanisms that modulate the innate immunity in annelids, whose alteration could affect their tolerance to microbial infection.

RESPUESTAS INMUNOLÓGICAS, ESTABILIDAD LISOSOMAL Y FRECUENCIA DE MICRONÚCLEOS EN Eurythoe complanata (POLYCHAETA: AMPHINOMIDAE) EXPUESTOS A UNA FRACCIÓN ACUOSA DE LUBRICANTES USADOS DE MOTORES DE AUTOMÓVILES

La viabilidad y numero total de celomocitos (NTC), actividad fagocitica y de lisozimas, estabilidad de las membranas lisosomales (EML), y frecuencia de micronucleos (FMN) en celomocitos fueron evaluados en el poliqueto Eurythoe complanata expuesto a una fraccion acuosa de lubricantes usados de motores de automoviles (FALUMA) al 3 % y a 200 µg/L de cadmio (Cd), de manera independiente, durante 21 dias. Adicionalmente, se estimaron la masa corporal y los cocientes moleculares de crecimiento (proteina/ARN, proteina/ADN y ARN/ADN). El NTC y la actividad fagocitica disminuyeron en los poliquetos en presencia de FALUMA, asociados con mayor desestabilizacion de las membranas lisosomales y FMN, lo cual no ocurrio en los organismos expuestos a Cd. La actividad bacteriolitica de lisozimas, la masa corporal y los cocientes proteina/ARN y ARN/ADN no variaron entre los organismos experimentales; solo se mostro un ligero incremento de proteina/ADN en organismos expuestos a FALUMA, lo que indica aumento de la sintesis de proteinas. Los parametros celulares e inmunologicos, EML, FMN y cociente proteina/ADN en el poliqueto E. complanata presentaron sensibilidad a la mezcla de xenobioticos hidrosolubles, por lo que constituyen biomarcadores importantes en la evaluacion de ambientes impactados por esta mezcla de contaminantes