Effects of membrane-perturbing drugs and noradrenalin on cAMP accumulation and red cell water content in carp (Cyprinus carpio) red cells

• 1.1. Carp red cells were treated with drugs that affect the cell membranes. The water content of the cells and the accumulation of cAMP in the cells were measured in normoxia and in hypoxia using non-stimulated and adrenergically stimulated cells.
• 2.2. WGA, DIDS + CCCP and A23187 increased the water content of nonstimulated normoxic cells.
• 3.3. In hypoxia ouabain and DIDS + CCCP increased the water content but cytochalasin B, NPM, DIDS, CCCP and A23187 + CA²⁺ abolished the hypoxia-induced swelling.
• 4.4. Any membrane perturbation induced some cAMP formation, Sophora and Anquilla lectins being most potent.
• 5.5. Also in adrenergically stimulated cells, membrane perturbation generally increased cAMP formation.
• 6.6. However, cAMP accumulation diminished in cells treated with cytochalasin B, CCCP and DIDS + CCCP.
• 7.7. The adrenergic swelling of carp red cells was reduced in normoxia by DIDS. NPM and CCCP increased the adrenergic swelling in normoxia to hypoxic level.
• 8.8. In hypoxia WGA and Anquilla lectin decreased the swelling.

     

Variations in tissue reserves,plasma metabolites and pancreatic hormones during fasting in immature carp (Cyprinus carpio)

• 1.1. Immature carp were subjected to 2-month fasting periods. Mobilization of reserves in liver and muscle, and the energy contribution of each reserve were studied. Changes in plasma glucose, amino acids, insulin and glucagon levels were determined throughout the experiment.
• 2.2. No changes were observed in plasma glucose, insulin or glucagon at 19 days of fasting, but plasma amino acids increased. At 50 days of fasting, both plasma glucagon and amino acids increased, liver glycogen decreased and muscle proteolysis began.
• 3.3. Between 50 and 67 days of fasting, plasma glucose and insulin decreased significantly, while glucagon and amino acids continued to increase. Strong muscular proteolysis was observed while liver glycogen stabilized.
• 4.4. The contribution of each reserve in liver and muscle to energy production throughout fasting is considered.

     

Electrolyte changes,cell volume regulation and hormonal influences during acclimation of rainbow trout (Salmo gairdnerii) to salt water

• 1.1. Rainbow trout were acclimated to salt water (1.5, 2.0 or 3.0%, which means 40, 60 or 85% concentrated sea-water) and the electrolyte, glucose and cortisol concentrations of the plasma as well as the extra- and intracellular muscle space, the muscle electrolyte concentrations and the ATPase activity were analysed.
• 2.2. Plasma osmolality, Na⁺, Ca²⁺ and Mg²⁺ concentrations of the plasma had a maximum at 24 hr after the start of acclimation when acclimated to 3.0% salt water. Plasma osmolality, Na⁺ and Mg²⁺ concentrations were significantly higher during the whole acclimation time when exposed to 3.0% salt water.
• 3.3. Variations and regulations of ECS and ICS were clearly demonstrated. The intracellular electrolyte concentrations were also maximal at 24 hr.
• 4.4. The plasma glucose level was just slightly elevated, but the cortisol level clearly indicated a stress response at 24 hr.
• 5.5. The activity of gill Na-K-ATPase increased during the acclimation time.
• 6.6. The regulatory processes in trout during acclimation to salt water are compared with those occurring in tilapia and carp.

     

Difference in the specific activity of tritium labelled water in blood,urine and evaporative water in rabbits

• 1.1. After a single injection of tritium labelled water (THO) into rabbits the specific activity was measured in blood, urine and evaporative water.
• 2.2. The specific activity in urine was similar to that in blood, the specific activity in pulmocutaneous evaporate was 5–8% below that of blood.
• 3.3. The permeability coefficient of the urinary bladder wall for THO was 44 ± 11 cm/sec × 10⁻⁶.
• 4.4. Maximum differences in the specific activity between blood and urine due to the accumulation of urine in the bladder were calculated as up to 1.8%.
• 5.5. In the state of equilibrium the specific activity in urine water, but not in evaporative water. can be used for the estimation of total body water.

     

Mucus as a diffusion barrier to oxygen: Possible role in O2 uptake at low pH in carp (Cyprinus carpio) gills

• 1.1. The standard V_o2 of carp (Cyprinus carpio) is reduced at low pH, concurrently with the formation of mucus on the gills.
• 2.2. The rate of diffusion of oxygen through mucus produced by carp in response to low pH was measured in a diffusion chamber and found to be 2.60 × 10⁻⁵ cm²/min per atm. The diffusion constant for water measured with the same apparatus was 3.60 × 10⁻⁵cm₂/min per atm.
• 3.3. The inhibition of the diffusion of oxygen into the gill bloodstream, and the inhibition of the flow of respiratory water between the secondary lamellae, are calculated for a gill with assumed dimensions. At thicknesses of mucus on the gills up to 5 μm the effects are similar, but at greater thicknesses the effect of slowing the water flow predominates. We conclude that mucus on the gills contributes to the hypoxia observed in fish subjected to high acidities.

     

Effect of experimental ventilation of the skin on cutaneous oxygen uptake in the carp,Cyprinus carpio

• 1.1. Cutaneous O₂ uptake in the carp, Cyprinus carpio, was determined at various water flow rates across the skin (.V) ranging from 2.5 to 40 ml/min, using flow-through respirometers.
• 2.2. When thickness of water flow was 2mm, cutaneous O₂ uptake remained stable (about 3.8 nmol/cm²/min) at a .V of 20–40 ml/min and decreased with .V below 20 ml/min.
• 3.3. When thickness of water flow was 4 mm, cutaneous O₂ uptake decreased with .V below 40 ml/min.
• 4.4. Apparent water velocity (U') was calculated dividing .V by an area of a cross section of the water flow (0.5 and 1.0 cm² respectively). In both experiments, cutaneous O₂ uptake decreased with U' below 0.7 cm/sec.
• 5.5. This suggests that cutaneous O₂ uptake in the carp is limited at a low water velocity by a resistance of the hypoxic boundary layer.

     

Factors regulating the functioning of the in vitro perfused aglomerular kidney of the anglerfish,Lophius piscatorius L.

• 1.1. Kidneys of Lophius were perfused from the renal portal vein with a Ringer's solution.
• 2.2. Mammalian and piscine neurohypophysial hormones (in doses of 20–500 ng/kg body wt) did not affect the rate of urine production or the urinary concentration of inorganic ions.
• 3.3. The rate of urine production and the urinary concentration of magnesium and sodium ions varied with the concentration of magnesium in the perfusate.
• 4.4. The rate of urine production was positively correlated with urine magnesium concentration (r = 0.83 ± 0.04) and negatively correlated with that of sodium (r = −0.40).
• 5.5. The urinary concentration of sodium ions varied inversely with that of magnesium ions (r = −0.89).
• 6.6. Ouabain treatment (0.1–0.8 mM/l) reduced the rate of urine production by over 60% and altered, to varying extents, the pattern of electrolyte excretion. A simple model for the mode of formation of urine by the aglomerular kidney, based on the present results and other observations is suggested.

     

Comparative aspects of the assay of carp gonadotropin

• 1.1. Estimation of gonadotropin content of five batches of carp pituitaries by three assay systems yielded similar relative potencies. The assays differed in their estimates of absolute pituitary gonadotropin content.
• 2.2. Carp gonadotropin was found to be more potent than salmonid gonadotropins in a bioassay based on cyclic AMP accumulation in immature grass carp ovary.

     

Physiological responses to exercise and hypoglycaemia stress in pigs of differing adrenal responsiveness

• 1.1. Twelve Large White × Landrace male pigs, six with high adrenocortical response to ACTH, and six with low response, were subjected to mild and moderate exercise, and then to insulin-induced hypoglycaemia.
• 2.2. Plasma ACTH, cortisol, catecholamines and some haematological and plasma biochemical parameters were determined in response to exercise, and glucose and cortisol in response to insulin challenge.
• 3.3. High responders had significantly greater increases than low responders in ACTH, cortisol and catecholamines following exercise, and in cortisol following insulin challenge.
• 4.4. The results suggest that differences in adrenocortical response to exogenous ACTH are an accurate reflection of the animal's response to stressful stimuli.

     

DNase-I-like enzyme from the carp liver—Inhibition by muscle and endogenous actin

• 1.1. DNase-I-like activity occurs in the carp (Cyprinus carpio) liver cytosol (supernatant 105,000g).
• 2.2. The enzyme resembles DNase I from bovine pancreas in respect to the molecular mass (~31 kDa), pH (7.4) and ion requirements (Mg²⁺, Ca²⁺) and the ability to degrade native as well as denatured DNA.
• 3.3. As judged by comparison of DNase zymograms obtained after native- and SDS-PAGE, the enzyme occurs in the three molecular forms of similar molecular weight and different charges.
• 4.4. All these forms are inhibited by rabbit skeletal muscle actin as well as by endogenous actin isolated from the carp liver cytosol.
• 5.5. DNase from the carp liver cytosol does not interact with the antibodies directed against DNase I from bovine pancreas and against DNase I from the rat and bovine parotid glands.

     

Glomerular filtration rate in saline acclimated ducks,gulls and geese

• 1.1. Glomerular filtration rate was estimated by measurement of cloacal excretion of intramuscularly injected ¹⁴C PEG in fresh water and sea water acclimated Mallards, Anas platyrhynchos, Canada Geese, Branta canadensis, and Glaucous-winged Gulls, Larus glaucescens.
• 2.2. GFR (ml/min kg) of FW Mallards was 3.3 ± 1.8 (5); FW geese, 1.2 ± 0.1 (2) and FW gulls, 1.9 ± 0.4(4).
• 3.3. Acclimation to SW did not affect the GFR of ducks, but increased the GFR of geese, 2.2 ± 0.1 (2) (P < 0.0005) and gulls, 4,0 ± 0.3 (5) (P < 0.005).

     

In vivo responses in plasma osmolality,and intracellular water and solute concentrations in flounder (Platichthys flesus) heart ventricles under acclimation to fresh and sea water

• 1.1. Flounders transferred abruptly from sea to fresh water displayed a gradual decrease in plasma osmolality for 5–6 days (10–15 mOsm daily). When returned to sea water the osmolality increased to the original level within 1 day.
• 2.2. Heart ventricle cell water content remained unchanged during the acclimations, except for a temporary 1.4% reduction within the first 4 hr of sea water acclimation.
• 3.3. During acclimation to sea water intracellular K⁺ increased rapidly in parallel with plasma osmolality. During fresh water acclimation, however, cellular K⁺ decreased rapidly in the first day only, whereas plasma osmolality decreased further.
• 4.4. Cellular taurine remained unchanged during the initial 4 days of fresh water acclimation and then declined 32% within the next 3 days. Upon retransfer to sea water, cellular taurine increased gradually to its original level in the course of 7 days.

     

Epidermal growth factor alters the electrolyte profile of lactating ewes Ovis aries

• 1.1. Lactating ewes were treated with mouse epidermal growth factor (EGF) at a dose rate of 0.5 mg/day for 4 days and its effects on the electrolyte profile were observed.
• 2.2. There was no effect of EGF on plasma concentrations of sodium or potassium, although urinary and total (in urine and milk) losses of both were reduced.
• 3.3. EGF-induced hypocalcaemia was associated with reduced milk calcium secretion and increased urinary calcium excretion whereas EGF-induced hypermagnesaemia was associated with reduced urinary and total magnesium losses.
• 4.4. Glomerular filtration rate was reduced during EGF infusion.
• 5.5. Chronic intravenous EGF infusion affects the electrolyte profile by altering electrolyte secretion by the mammary gland and renal electrolyte excretion.

     

Oral administration of insulin in winter-acclimatized carp (Cyprinus carpio) induces hepatic ultrastructural changes

• 1.1. The intestinal absorption of insulin in carps was assessed examining the transepithelial passage of ingested gold-labeled hormone by electron microscopy. Insulin transfer occurred mainly through the intercellular spaces between the enterocytes.
• 2.2. When reaching the lamina propria, the gold-labeled hormone gathered predominantly around the granules of the granular cells, and therefore can enter the circulatory system via the blood capillaries which are found in close contact with these cells.
• 3.3. Winter-acclimatized carp were also capable of internalizing the hormone when fed with insulin.
• 4.4. Furthermore, the absorbed hormone revealed full activity in regard to the observed changes in the ultrastructure of the liver cells of the treated cold-adapted fish.
• 5.5. The fish ingesting the hormone underwent the same type of hepatic ultrastructure reprogramming observed when winter-acclimatized carps are injected intraperitoneally with insulin, i.e. conversion to a phenotype corresponding to hepatocytes from summer-adapted carp.
• 6.6. The oral absorption of insulin by winter-acclimatized fish and its effect in reversing the cold-adaptive state might be useful for the fish culturing industry.

     

Effects of angiotensin II and bladder condition on hydration behavior and water uptake in the toad,Bufo woodhousei

• 1.1. Water absorption response (WR) behavior and water weight gain were examined in hydrated toads, Bufo woodhousei, treated with angiotensin II (All) or with a control Ringer's solution. The effects of urinary bladder condition (ad lib. bladder urine or empty bladder) were examined concurrently.
• 2.2. Toads treated with All (100μg/100g body weight), spent more time in WR posture and absorbed more water than Ringer's-injected toads.
• 3.3. Toads with empty bladders maintained WR posture for longer periods of time and gained more weight than toads whose bladders were not emptied.
• 4.4. The effects of All and bladder urine on water absorption by B. woodhousei appear to be separate and additive.

     

Clastogenic effects of five carcinogenicmutagenic chemicals on the cells of the common carp,cyprinus carpio L.

• 1.1. The cytogenetic effects of various i.p. treatments with five carcinogenic-mutagenic chemicals and three doses for each (aflatoxin Bl, Aroclor 1254, benzidine, benzo[a]pyrene and 20-methylcholanthrene), were investigated in the cells of the common carp, Cyprinus carpio.
• 2.2. Injection with distilled water and corn oil served as the two control groups.
• 3.3. For detecting cytogenetic damage we used two test systems, chromosomal aberrations (CA) in kidney cells and micronucleated erythrocytes (M).
• 4.4. At 48 hr after treatment with the chemicals under investigation, the frequencies of CA and M were clearly increased in a dose-response manner compared to the control groups.

     

Changes in blood metabolite concentrations in response to repeated capture,anaesthesia and blood sampling in the golden perch,Macquaria ambigua

• 1.1. The major metabolic changes associated with repeated capture, aquarium transfer, anaesthesia and blood sampling were investigated in an Australian freshwater fish, the golden perch (Macquaria ambigua),
• 2.2. A compounded stress response was seen after repetition of the procedure, in which the plasma glucose rose within 3 hr and amino acid concentrations rose and the serum free fatty acids concentration fell after 24 hr.
• 3.3. Alanine was identified as an important circulating energy store in the stress response of golden perch.
• 4.4. No change was noted in the serum protein, plasma lactate or β-hydroxybutyrate concentrations, indicating that tissue damage and hypoxia were absent, and that degradation of free fatty acids did not produce metabolites excess to the requirements of gluconeogenesis and the tricarboxylic acid cycle.

     

The effect of dietary protein level and ration level on excretion of ammonia in common carp,Cyprinus carpio

• 1.1. Nitrogenous excretion in the form of ammonia was determined in common carp of 65.0 ± 8.0 g body weight in metabolism chambers. The fish were fed with 20, 35 and 50% dietary protein at 1, 2 and 3% body weight per day ration level.
• 2.2. Nitrogenous excretion as a percentage of ingested food increased with an increase of dietary protein but decreased with an increase of ration level.
• 3.3. The energy lost in excretion ranged from 4.19% with 20% dietary protein at 3% ration level to 8.74% with 50% dietary at 1% ration level.

     

Oxidative metabolism of the inner and outer ventricular layers of carp heart (Cyprinus carpio L.)

• 1.1. The biochemical characteristics of homogenates and mitochondria isolated from the outer and inner layers of the ventricular myocardium of carp were studied.
• 2.2. The homogenate prepared from the inner layer exhibited higher activity of cytochrome oxidase than that from the outer layer. No difference was found in the activity of cytochrome oxidase between mitochondria from the inner and outer layers. Difference spectra of cytochromes also showed that their content in mitochondria of both layers is similar and that the higher oxidative capacity of the spongious layer is due to a higher content of mitochondria.
• 3.3. In comparison with rat heart a higher content of cyt aa₃ and a lower content of Cyt b and cyt cc₁ were found in carp heart mitochondria.
• 4.4. In comparison with rat heart, carp heart mitochondrial enzymes were more sensitive to freezing-thawing and to detergent action.

     

The effect of osmotic and ion-osmotic stresses on the blood and urine composition and urine flow of rainbow trout (Salmo gairdneri)

• 1.1. Changes in urine and plasma concentrations (sodium, potassium, magnesium, calcium and total osmotic) and urine production were determined in fish exposed to various concentrations of an ionically active substance, sodium chloride, and a non-electrolyte, mannitol, as well as freshwater.
• 2.2. Responses occurred for the most part over a short crisis period preceeding establishment of new stable conditions.
• 3.3. It was shown that plasma homeostasis was not maintained in response to changing ion-osmotic and osmotic gradients.
• 4.4. Urinary osmotic and ionic concentrations were unaffected and urine production was shown to be inversely related to the external concentration.
• 5.5. It is suggested that ionic shifts between body compartments are an important aspect of ion-osmotic adaptation.