Resource allocation and extracellular acid–base status in the sea urchin Strongylocentrotus droebachiensis in response to CO2 induced seawater acidification

Using the critical salinity (S crit) concept to predict invasion potential of the anemone Diadumene lineata in the Baltic Sea

“…Similar observations of reductions in the scope for growth due to stable respiration rates while feeding rates decreased simultaneously have been made in other marine invertebrates during exposure to environmental stress (Stumpp et al 2012;Appelhans et al 2014). Thus, saving energy by reducing food intake and digestion as well as the subsequent anabolic processes (protein turnover for growth) seems to be a common strategy in marine invertebrates exposed to stress.…”

Ocean acidification and temperature rise: effects on calcification during early development of the cuttlefish Sepia officinalis

“…stage at which abilities to regulate the internal coelomic fluid pH by modulating bicarbonate accumulation were observed (sea urchin: Stumpp et al 2012). In this same group (Beniash et al 1997, 1999, Politi et al 2004 and recently in bivalves (Weiss et al 2002, Jacob et al 2011 shown that the initial stages of calcification are intracellular processes: an amorphous calcium carbonate (ACC) precursor phase is formed in vesicles and later exocytosed to be incorporated into the skeleton (see Addadi et al 2006 for a review of current concepts).…”

Recent advances in understanding trans-epithelial acid-base regulation and excretion mechanisms in cephalopods

“…In this context, the coupling of NH 4 C excretion and proton secretion could represent a fundamental pathway to directly excrete protons from extracellular fluids in marine invertebrates. 12,29,112,120,121 This hypothesis is supported by the fact that a range of marine species including molluscs, 121 echinoderms 30,31 and crustaceans 29 increase NH 4 C excretion rates in response to acidified conditions. Recently established perfusion techniques using isolated gills of octopus represent a technical breakthrough to study pH regulation (e.g., proton transport rates v.s.…”

“…[26][27][28][29] Although less active marine invertebrates were generally shown to have lower capabilities to compensate for extracellular acid-base disturbances, some echinoderms including sea urchins (Strongylocentrotus droebachiensis) and brittle stars (Amphiura filiformis) were demonstrated to be able to control extracellular pH to a certain degree. 30,31 The acid-base compensatory mechanism in these species is predominantly achieved through the accumulation of bicarbonate in body fluids, as well as an increased excretion of protons and/or proton equivalents (NH 4 C ). 30,31 Similar to fish and crustaceans, also adult cuttlefish (Sepia officinalis) and squid (Sepioteuthis lessoniana) can compensate for an extracellular acidosis when exposed to elevated environmental pCO 2 by actively increasing blood [HCO 3 ¡ ] levels.…”

“…30,31 The acid-base compensatory mechanism in these species is predominantly achieved through the accumulation of bicarbonate in body fluids, as well as an increased excretion of protons and/or proton equivalents (NH 4 C ). 30,31 Similar to fish and crustaceans, also adult cuttlefish (Sepia officinalis) and squid (Sepioteuthis lessoniana) can compensate for an extracellular acidosis when exposed to elevated environmental pCO 2 by actively increasing blood [HCO 3 ¡ ] levels. The compensation reaction happens within few hours and can lead to a partial compensation in S. officinalis accompanied by an increase in blood [HCO 3 ¡ ] from 3.4 to 10.4 mM 13 or a full compensation of blood pH as found in S. lessoniana with an increase in blood [HCO 3 ¡ ] from 2.3 to 4.3 mM.…”