The metabolic responses and acid–base status after feeding, exhaustive exercise, and both feeding and exhaustive exercise in Chinese catfish (Silurus asotus Linnaeus)

The intracellular acid-base status of white muscle of freshwater (FW) and seawater (SW) -adapted rainbow trout was examined before and after exhaustive exercise. Exhaustive exercise resulted in a pronounced intracellular acidosis with a greater pH drop in SW (0.82 pH units) than in FW (0.66 pH units) trout; this was accompanied by a marked rise in intracellular lactate levels, with more pronounced increases occurring in SW (54.4 mmoll−1) than in FW (45.7 mmoll−1) trout. Despite the more severe acidosis, recovery was faster in the SW animals, as indicated by a more rapid clearance of metabolic H+ and lactate loads. Compartmental analysis of the distribution of metabolic H+ and lactate loads showed that the more rapid recovery of pH in SW trout could be due to (1) their greater facility for excreting H+ equivalents to the environmental water [e.g. 15.5 % (SW) vs 5.0 % (FW) of the initial H+ load was stored in external water at 250 min post-exercise] and, to a greater extent, (2) the more rapid removal of H+, facilitated via lactate metabolism in situ (white muscle) and/or the Cori cycle (e.g. heart, liver). The slower pH recovery in FW trout may also be due in part to greater production of an ‘unmeasured acid’ [maximum approx. 8.5 mmol kg−1 fish (FW) vs approx. 6 mmol kg−1 fish (SW) at 70–130 min post-exercise] during the recovery period. Furthermore, the analysis revealed that H+-consuming metabolism is quantitatively the most important mechanism for the correction of an endogenously originating acidosis, and that extracellular pH normalization gains priority over intracellular pH regulation during recovery of acid-base status following exhaustive exercise.

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The Role of β-Adrenoreceptors in the Recovery from Exhaustive Exercise of Freshwater-Adapted Rainbow Trout

Journal of Experimental Biology ◽

10.1242/jeb.147.1.471 ◽

1989 ◽

Vol 147 (1) ◽

pp. 471-491 ◽

Cited By ~ 1

Author(s):

D. G. MCDONALD ◽

Y. TANG ◽

R. G. BOUTILIER

Keyword(s):

Rainbow Trout ◽

Exhaustive Exercise ◽

Acid Base ◽

Post Exercise ◽

Nacl Concentration ◽

Adrenergic Mechanism ◽

Acid Base Status ◽

Isoproterenol Infusion ◽

Net Fluxes

Rainbow trout, fitted with arterial catheters, were exercised to exhaustion by manual chasing and then injected with either saline (controls), the β-agonist isoproterenol or the β-antagonist propranolol. Blood acid-base status, branchial unidirectional and net fluxes of Na+ and Cl−, and net fluxes of ammonia and acidic equivalents (JHnet) were monitored over the subsequent 4 h of recovery. These same parameters were also monitored in normoxic, resting fish following isoproterenol injection and in exercised fish following acute post-exercise elevation of external NaCl concentration. In addition to confirming an important role for β-adrenoreceptors in the regulation of branchial gas exchange and red cell oxygenation and acid-base status, we find a significant β-adrenergic involvement in the flux of lactic acid from muscle and in JHnet across the gills. Both isoproterenol infusion (into nonexercised fish) and exhaustive exercise were found to cause net acid excretion. The post-exercise JHnet was further augmented by elevating [NaCl] but was not affected, in this instance, either by β-stimulation or blockade, indicating that JHnet was not entirely regulated by a β-adrenergic mechanism. On the basis of a detailed analysis of unidirectional Na+ and Cl− fluxes, we conclude that the increase in JHnet following exercise arose mainly from increased Na+/H+(NH4+) exchange and that the upper limit on JHnet was set by the supply of external counterions and by the increase in branchial ionic permeability that invariably accompanies exhaustive exercise.

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Intracellular and extracellular acid-base status and H+ exchange with the environment after exhaustive exercise in the rainbow trout

Journal of Experimental Biology ◽

10.1242/jeb.123.1.93 ◽

1986 ◽

Vol 123 (1) ◽

pp. 93-121 ◽

Cited By ~ 3

Author(s):

C. L. Milligan ◽

C. M. Wood

Keyword(s):

Rainbow Trout ◽

Venous Blood ◽

Extracellular Fluid ◽

Exhaustive Exercise ◽

Whole Body ◽

Acid Base ◽

Acid Load ◽

Acid Base Status ◽

Lactate Levels ◽

Exercise Induced

Exhaustive exercise induced a severe short-lived (0–1 h) respiratory, and longer-lived (0–4 h) metabolic, acidosis in the extracellular fluid of the rainbow trout. Blood ‘lactate’ load exceeded blood ‘metabolic acid’ load from 1–12 h after exercise. Over-compensation occurred, so that by 8–12 h, metabolic alkalosis prevailed, but by 24 h, resting acid-base status had been restored. Acid-base changes were similar, and lactate levels identical, in arterial and venous blood. However, at rest venous RBC pHi was significantly higher than arterial (7.42 versus 7.31). After exercise, arterial RBC pHi remained constant, whereas venous RBC pHi fell significantly (to 7.18) but was fully restored by 1 h. Resting mean whole-body pHi, measured by DMO distribution, averaged approx. 7.25 at a pHe of approx. 7.82 and fell after exercise to a low of 6.78 at a pHe of approx. 7.30. Whole-body pHi was slower to recover than pHe, requiring up to 12 h, with no subsequent alkalosis. Whole-body ECFV decreased by about 70 ml kg-1 due to a fluid shift into the ICF. Net H+ excretion to the water increased 1 h after exercise accompanied by an elevation in ammonia efflux. At 8–12 h, H+ excretion was reduced to resting levels and at 12–24 h, a net H+ uptake occurred. Lactate excretion amounted to approx. 1% of the net H+ excretion and only approx. 2% of the whole blood load. Only a small amount of the anaerobically produced H+ in the ICF appeared in the ECF and subsequently in the water. By 24 h, all the H+ excreted had been taken back up, thus correcting the extracellular alkalosis. The bulk of the H+ load remained intracellular, to be cleared by aerobic metabolism.

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Sustained swimming at low velocity following a bout of exhaustive exercise enhances metabolic recovery in rainbow trout

Journal of Experimental Biology ◽

10.1242/jeb.203.5.921 ◽

2000 ◽

Vol 203 (5) ◽

pp. 921-926 ◽

Cited By ~ 7

Author(s):

C.L. Milligan ◽

G.B. Hooke ◽

C. Johnson

Keyword(s):

Rainbow Trout ◽

Plasma Cortisol ◽

Enhanced Recovery ◽

Recovery Period ◽

Cortisol Concentration ◽

Exhaustive Exercise ◽

Active Recovery ◽

Acid Base ◽

Low Velocity ◽

Acid Base Status

Sustained swimming at 0.9 BL s(−)(1), where BL is fork body length, following a bout of exhaustive exercise enhanced recovery of metabolite and acid-base status in rainbow trout compared with fish held in still water. The most striking effect of an active recovery was a total absence of the elevation cortisol concentration typically associated with exhaustive exercise. In fish swimming at 0. 9 BL s(−)(1), plasma cortisol levels averaged 20–25 ng ml(−)(1) throughout the 6 h recovery period. In contrast, plasma cortisol increased to a peak level of 128.4+/−11.2 ng ml(−)(1) (mean +/− s.e. m., N=6) in fish recovering in still water. Muscle glycogen was completely resynthesized and lactate cleared within 2 h of exercise in swimming fish compared with more than 6 h required in the fish held in still water. Similarly, blood lactate level and acid-base status were restored more quickly in the swimming fish. These observations suggest that the prolonged recovery usually associated with exhaustive exercise in rainbow trout is due to elevations in plasma cortisol concentration and that the stimulus for cortisol release is not exercise per se, but rather post-exercise inactivity.

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To Manage Infantile Hypertrophic Pyloric Stenosis by "Double-Y Pyloromyotomy" is a better Surgical Approach

Journal of Paediatric Surgeons of Bangladesh ◽

10.3329/jpsb.v1i2.19532 ◽

2014 ◽

Vol 1 (2) ◽

pp. 143-147

Author(s):

Md. Ansar Ali ◽

Kaniz Hasina ◽

Shahnoor Islam ◽

Md. Ashraf Ul Huq ◽

Md. Mahbub-Ul Alam ◽

...

Keyword(s):

Weight Gain ◽

Pyloric Stenosis ◽

Hypertrophic Pyloric Stenosis ◽

Treatment Modalities ◽

Infantile Hypertrophic Pyloric Stenosis ◽

Postoperative Vomiting ◽

Acid Base ◽

Feeding Regimes ◽

Acid Base Status ◽

Postoperative Feeding

Background: Different treatment modalities and procedures have been tried for the management of infantile hypertrophic pyloric stenosis. But surgery remains the mainstay for management of IHPS. Ramstedts pyloromyotomy was described almost over a hundred years ago and to date remains the surgical technique of choice. An alternative and better technique is the double-Y pyloromyotomy, which offer better results for management of this common condition.Methods: A prospective comparative interventional study of 40 patients with IHPS was carried out over a period of 2 years from July 2008 to July 2010. The patients were divided into 2 equal groups of 20 patients in each. The study was designed that all patients selected for study were optimized preoperatively regarding to hydration, acid-base status and electrolytes imbalance. All surgeries were performed after obtaining informed consent. Standard preoperative preparation and postoperative feeding regimes were used. The patients were operated on an alternate basis, i.e., one patient by Double-Y Pyloromyotomy(DY) and the next by aRamstedts Pyloromyotomy (RP). Data on patient demographics, operative time, anesthesia complications, postoperative complications including vomiting and weight gain were collected. Patients were followed up for a period of 3 months postoperatively. Statistical assessments were done by using t test.Results: From July 2008 through July 2010, fourty patients were finally analyzed for this study. Any statistical differences were observed in patient population regarding age, sex, weight at presentation, symptoms and clinical condition including electrolytes imbalance and acid-base status were recorded. Significant differences were found in postoperative vomiting and weight gain. Data of post operative vomiting and weight gain in both groups were collected. Vomiting in double-Y(DY) pyloromyotomy group (1.21 ± 0.45days) vs Ramstedts pyloromyotomy (RP) group(3.03 ± 0.37days) p= 0.0001.Weight gain after 1st 10 days DY vs RP is ( 298 ± 57.94 gm vs193±19.8 gm p=0.0014), after 1 month (676.67±149.84 gm vs 466.67 ± 127.71 gm, p=0.0001), after 2months (741.33± 278.74 gm vs 490±80.62 gm, p=0.002) and after 3 months (582±36.01gm vs 453.33±51.64 gm, p=0.0001).No long-term complications were reported and no re-do yloromyotomy was needed.Conclusion: The double-Y pyloromyotomy seems to be a better technique for the surgical management of IHPS. It may offer a better functional outcome in term of postoperative vomiting and weight gain.DOI: http://dx.doi.org/10.3329/jpsb.v1i2.19532

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