Intraespecific differences in the antioxidant capacity in the copepod Boeckella gracilipes of Andean lakes and consequences in metabolic enzymes.

BALSEIRO, E.G; LASPOUMADERES, C.; SOUZA, M.S.; BASTIDAS NAVARRO, M.; MODENUTTI, B.E.

Congreso; ASLO Summer Meeting 2011; 2011

Calanoid copepods are dominant zooplankters in many nutrient poor mountain lakes. In these ecosystems, high C:P ratios are associated with high light-phosphorus ratios, thus, organisms living in these transparent lakes would be constrained by potentially hazardous ultraviolet radiation (UVR). This situation will cause a reduced antioxidant capacity that would affect other physiological processes, such specific enzymatic endpoints as Acetylcholinesterase (AChE).  A dysfunction of AChE would affect copepod motility patterns and consequently the copepod’s fitness. Here, we analyzed this deleterious effect in the copepod Boeckella gracilipes a widespread species in Andean North Patagonian lakes. We performed field and laboratory experiments determining elemental ratios, enzyme activities and first antennae (A1) damage. We also carried out feeding rate measurements, as a way to estimate copepod fitness. Our results showed that UVR cause dysfunctions in AChE and A1 was indeed affected.  Changes in UVR levels as well as in elemental ratios will affect cellular mechanisms that will have important consequences in organism’s functioning such as movement capacity.