“Biochemical and physiological flexibility in the euryhaline semiterrestrial crab Neohelice granulata from contrasting habitats”

PINONI,S.; LÓPEZ MAÑANES, A.A.

Encuentro; XXVII Annual Scientific Meeting Tucumán Biology Association; 2010

Biochemical-physiological adjustments allowing the occupancy of constrating habitats by N. granulata are unknown. We determined hemolymph (HL) osmolality, and muscle (M) and hepatopancreas (HP) triglycerides concentration (TG) in crabs from mudflat (MF) and saltmarsh (SM) of Mar Chiquita coastal lagoon (Bs. As. Province). Adult male crabs were acclimated for 10 days to 6, 10, 35, 45 and 60‰ salinity (S). HL and medium (m) osmolality (mOsmxkg-1) were determined with cryoscopic osmometer. TG (mgxg tissue-1) were determined (Kit Wiener-Lab AA) in homogenates from M (sucrose 0.25M/EGTA-Tris 0.5mM, pH7.4, 8 mlxg tissue-1) and HP (Tris-HCl 0.1M, pH7.4, 4mlxg tissue-1). MF and SM crabs showed similar osmoregulatory pattern: hiperegulation: 6 (m:144±31, HL:MF=620±45;SM=725±21) and 10 S (m:316±5,HL:MF=660±34,SM=704±17); osmoconformation: 35 S (m:932±21; HL:MF=837±31, SM=829±17); hyporegulation: 45 (m:1191±12;HL:MF=868±40,SM=795±22); 60 S (m:1708±17; HL:MF=1158±84, SM=1112±61) (n=6, t-test, p