A role for adenosine in metabolic depression in the marine invertebrate Sipunculus nudus

The modulatory effects of neurotransmitters on the metabolic rate of Sipunculus nudus were analyzed after the exposure of the nervous tissue of the marine invertebrate to anoxia or hypercapnia. Metabolic depression due to anoxia and hypercapnia reduced the levels of glutamate, glycine, taurine and monoamines in the nervous tissue of Sipunculus nudus. Furthermore, the marine invertebrate also exhibited extracellular acidosis in response to metabolic depression indicating the role of cellular mechanisms in mediating overall reductions in the metabolism of Sipunculus nudus.