Differential modulation of digestive enzymes and energy reserves at different times after feeding in juveniles of the marine estuarine-dependent flatfish Paralichthys orbignyanus (Valenciennes, 1839).

Integrative studies are lacking on the responses of digestive enzymes and energy reserves in conjunction with morphological traits at distinct postprandial times in marine estuarine-dependent flatfishes of ecological and economic importance, such as Paralichthys orbignyanus. We determined total weight (TW), hepato-somatic index (IH), activities of digestive enzymes in the intestine, and the concentration of energy reserves in the liver and the muscle at 0, 24, 72, and 360 h after feeding in juveniles of P. orbignyanus.

Glucose homeostasis in the euryhaline crab Cytograpsus angulatus: Effects of the salinity in the amylase, maltase and sucrase activities in the hepatopancreas and in the carbohydrate reserves in different tissues.

We studied the existence, biochemical characteristics and response to different environmental salinities of amylase, maltase and sucrase activity in the intertidal euryhaline crab Cyrtograpsus angulatus (Dana, 1852) along with the response to distinct salinities of glycogen and free glucose content in storage organs. Amylase, maltase and sucrase activities were kept over a broad range of pH and temperature and exhibited Michaelis-Menten kinetics. Zymography showed the existence of two amylase forms in crabs exposed to 35 (osmoconformation) and low (6-10psu; hyper-regulation) or high (40psu) (hypo-regulation) salinities.

Trypsin and N-aminopeptidase (APN) activities in the hepatopancreas of an intertidal euryhaline crab: Biochemical characteristics and differential modulation by histamine and salinity.

No studies are available about biochemical characteristics and modulation (i.e. by endogenous and/or environmental cues) of trypsin (a key digestive endoprotease) in hepatopancreas of intertidal euryhaline crabs neither on the possible concomitant modulation of key ectoproteases such as aminopeptidase-N (APN) involved in final steps of protein digestion.

Digestive flexibility in females of the subterranean rodent ctenomys talarum in their natural habitat.

We studied the occurrence of digestive strategies at different levels in females of the subterranean herbivorous rodent Ctenomys talarum living in their natural habitat. We determined the dimensions of different parts of the gastrointestinal tract and organs along as the activity of key digestive enzymes(sucrase, maltase and N-aminopeptidase) in small intestine in females seasonally caught. Females of C.

Between-habitat comparison of digestive enzymes activities and energy reserves in the SW Atlantic euryhaline burrowing crab Neohelice granulata.

The digestive and metabolic characteristics at the biochemical level underlying between-habitat dietary shift of the SW Atlantic euryhaline burrowing crab Neohelice granulata under natural conditions are unknown. We made studies on adult males of N. granulata from the open mudflat and the vegetated saltmarsh in a SW Atlantic costal lagoon (Mar Chiquita, 37°32'-37°45'S; 57°19'-57°26'W, Argentina).

Digestive strategies in the South American subterranean rodent Ctenomys talarum.

Ctenomys talarum is a subterranean herbivorous rodent which due to its particular life style is frequently exposed to variations in surface environmental conditions (i.e. food quality and availability, temperature).

Phenotypic plasticity in response to low quality diet in the South American omnivorous rodent Akodon azarae (Rodentia: Sigmodontinae).

We studied the responses in the omnivorous rodent A. azarae submitted to a low quality diet at morphological, physiological and biochemical levels. At short term, a decrease in body mass occurred.

Seasonal changes in body composition of Ctenomys talarum (Rodentia: Octodontidae): an herbivore subterranean rodent.

Ctenomys talarum is a subterranean herbivorous rodent whose burrow systems exhibit particular characteristics, distinct from other subterranean environments. We studied seasonal variation in body composition of C. talarum in relation to energetic requirements.

Phenotypic flexibility of digestive morphology and physiology of the South American omnivorous rodent Akodon azarae (Rodentia: Sigmodontinae).

We have determined the occurrence of responses at different levels (morphological, physiological and biochemical) in the omnivorous rodent Akodon azarae upon cold acclimation (15 degrees C). A short-term enhancement in food consumption appeared to account for the maintenance of both mass and body composition. At the morphological level, the main response was an increase in the dimensions of small intestine, which constitutes the section of the gut where absorption and secretion take place.