Effects of feeding on metabolism, gas transport, and acid-base balance in the bullfrog Rana catesbeiana

2000 ◽  
Vol 278 (1) ◽  
pp. R185-R195 ◽  
Author(s):  
Morten Busk ◽  
Frank B. Jensen ◽  
Tobias Wang

Massive feeding in ectothermic vertebrates causes changes in metabolism and acid-base and respiratory parameters. Most investigations have focused on only one aspect of these complex changes, and different species have been used, making comparison among studies difficult. The purpose of the present study was, therefore, to provide an integrative study of the multiple physiological changes taking place after feeding. Bullfrogs ( Rana catesbeiana) partly submerged in water were fed meals (mice or rats) amounting to ∼[Formula: see text] of their body weight. Oxygen consumption increased and peaked at a value three times the predigestive level 72–96 h after feeding. Arterial[Formula: see text] decreased slightly during digestion, whereas hemoglobin-bound oxygen saturation was unaffected. Yet, arterial blood oxygen content was pronouncedly elevated because of a 60% increase in hematocrit, which appeared mediated via release of red blood cells from the spleen. Gastric acid secretion was associated with a 60% increase in plasma [Formula: see text]concentration[Formula: see text]]) 48 h after feeding. Arterial pH only increased from 7.86 to 7.94, because the metabolic alkalosis was countered by an increase in[Formula: see text] from 10.8 to 13.7 mmHg. Feeding also induced a small intracellular alkalosis in the sartorius muscle. Arterial pH and [Formula: see text] returned to control values 96–120 h after feeding. There was no sign of anaerobic energy production during digestion as plasma and tissue lactate levels remained low and intracellular ATP concentration stayed high. However, phosphocreatine was reduced in the sartorius muscle and ventricle 48 h after feeding.

1980 ◽  
Vol 84 (1) ◽  
pp. 273-287
Author(s):  
D. G. McDonald ◽  
R. G. Boutilier ◽  
D. P. Toews

Strenuous exercise results in a marked blood acid-base disturbance which is accompanied by large increases in ventilation rate, heart rate and mean arterial blood pressure. Recovery to normal resting values follows an exponential time course with a half-time of approximately 2 h for all parameters except Pa, CO2 and ventilation rate. The latter return to normal by 30 min following the exercise period. Analysis reveals that there is initially a large discrepancy between the quantity of metabolic acids buffered in the blood and the blood lactate levels. The significance of this finding is discussed. Significant changes in the concentrations of chloride, bicarbonate and lactate, in both plasma and erythrocytes, accompany the blood acid-base disturbance. Chloride and bicarbonate appear to be passively distributed between the two compartments according to a Gibbs-Donnan equilibrium whereas lactate only slowly permeates the erythrocyte.


1981 ◽  
Vol 50 (4) ◽  
pp. 779-783 ◽  
Author(s):  
S. C. Wood ◽  
K. Johansen ◽  
M. L. Glass ◽  
R. W. Hoyt

Current concepts of acid-base balance in ectothermic animals require that arterial pH vary inversely with body temperature in order to maintain a constant OH-/H+ and constant net charge on proteins. The present study evaluates acid-base regulation in Varanus exanthematicus under various regimes of heating and cooling between 15 and 38 degrees C. Arterial blood was sampled during heating and cooling at various rates, using restrained and unrestrained animals with and without face masks. Arterial pH was found to have a small temperature dependence, i.e., pH = 7.66--0.005 (T). The slope (dpH/dT = -0.005), while significantly greater than zero (P less than 0.05), is much less than that required for a constant OH-/H+ or a constant imidazole alphastat (dpH/dT congruent to 0.018). The physiological mechanism that distinguishes this species from most other ectotherms is the presence of a ventilatory response to temperature-induced changes in CO2 production and O2 uptake, i.e., VE/VO2 is constant. This results in a constant O2 extraction and arterial saturation (approx. 90%), which is adaptive to the high aerobic requirements of this species.


PEDIATRICS ◽  
1970 ◽  
Vol 46 (5) ◽  
pp. 730-736
Author(s):  
Katherine H. Halloran ◽  
Steven C. Schimpff ◽  
Jean G. Nicolas ◽  
Norman S. Talner

Tolerance to acetyl strophanthidin, a rapid-acting cardiac aglycone, was determined in 28 anesthetized mongrel puppies, ages 16 to 56 days, and compared to tolerance in 16 littermate puppies in whom acute hypercapnic acidemia was produced. The tolerance was also compared to that of four adult mongrel dogs. The toxic dose was defined as the intravenous amount required to produce four consecutive premature ventricular contractions. A marked variation in the toxic dose was found in the 28 control puppies (range 83 to 353 µg/kg, mean 169 µg/kg) which could not be correlated with age, arterial blood gases or pH, serum potassium or sodium, arterial pressure, or heart rate. The toxic dose was significantly greater in the puppies than in the adult dogs, in whom the mean toxic dose was 64 µg/kg (range 50 to 89 µg/kg). A significant increase in tolerance was also observed in the puppies with hypercapnic acidemia (mean toxic dose 220 µg/kg, range 93 to 375 µg/kg) in comparison to tolerance in the control puppies and despite the wide range of tolerance, each of the puppies with hypercapnic acidemia showed greater tolerance than its littermate control puppy. Assessment of the clinical implications of these findings will require study of the effects of alterations in acid-base balance on the inotropic effect of acetyl strophanthidin in addition to the toxic electrophysiologic effects.


1977 ◽  
Vol 232 (1) ◽  
pp. R10-R17 ◽  
Author(s):  
R. G. DeLaney ◽  
S. Lahiri ◽  
R. Hamilton ◽  
P. Fishman

Upon entering into aestivation, Protopterus aethiopicus develops a respiratory acidosis. A slow compensatory increase in plasma bicarbonate suffices only to partially restore arterial pH toward normal. The cessation of water intake from the start of aestivation results in hemoconcentration and marked oliguria. The concentrations of most plasma constituents continue to increase progressively, and the electrolyte ratios change. The increase in urea concentration is disproportionately high for the degree of dehydration and constitutes an increasing fraction of total plasma osmolality. Acid-base and electrolyte balance do not reach a new equilibrium within 1 yr in the cocoon.


1981 ◽  
Vol 51 (2) ◽  
pp. 452-460 ◽  
Author(s):  
P. E. Bickler

The effects of constant and changing temperatures on blood acid-base status and pulmonary ventilation were studied in the eurythermal lizard Dipsosaurus dorsalis. Constant temperatures between 18 and 42 degrees C maintained for 24 h or more produced arterial pH changes of -0.0145 U X degrees C-1. Arterial CO2 tension (PCO2) increased from 9.9 to 32 Torr plasma [HCO-3] and total CO2 contents remained constant at near 19 and 22 mM, respectively. Under constant temperature conditions, ventilation-gas exchange ratios (VE/MCO2 and VE/MO2) were inversely related to temperature and can adequately explain the changes in arterial PCO2 and pH. During warming and cooling between 25 and 42 degrees C arterial pH, PCO2 [HCO-3], and respiratory exchange ratios (MCO2/MO2) were similar to steady-state values. Warming and cooling each took about 2 h. During the temperature changes, rapid changes in lung ventilation following steady-state patterns were seen. Blood relative alkalinity changed slightly with steady-state or changing body temperatures, whereas calculated charge on protein histidine imidazole was closely conserved. Cooling to 17-18 degrees C resulted in a transient respiratory acidosis correlated with a decline in the ratio VE/MCO2. After 12-24 h at 17-18 degrees C, pH, PCO2, and VE returned to steady-state values. The importance of thermal history of patterns of acid-base regulation in reptiles is discussed.


1980 ◽  
Vol 84 (1) ◽  
pp. 289-302
Author(s):  
R. G. Boutilier ◽  
D. G. McDonald ◽  
D. P. Toews

A combined respiratory and metabolic acidosis occurs in the arterial blood immediately following 30 min of strenuous activity in the predominantly skin-breathing urodele, Cryptobranchus alleganiensis, and in the bimodal-breathing anuran, Bufo marinus, at 25 degrees C. In Bufo, the bulk of the post-exercise acidosis is metabolic in origin (principally lactic acid) and recovery is complete within 4-8 h. In the salamander, a lower magnitude, longer duration, metabolic acid component and a more pronounced respiratory acidosis prolong the recovery period for up to 22 h post-exercise. It is suggested that fundamental differences between the dominant sites for gas exchange (pulmonary versus cutaneous), and thus in the control of respiratory acid-base balance, may underline the dissimilar patterns of recovery from exercise in these two species.


2018 ◽  
Vol 34 (1-2) ◽  
pp. 38-43
Author(s):  
Sari Leyli Harahap ◽  
Chairul Adillah Harahap ◽  
Sri Sulastri ◽  
Chairul Yoel ◽  
Noersida Raid

We performed a prospective study on the association between acid-base balance and asphyxta based on Apgar scores in 45 newborn babies admitted to the Division of Perinatology, Pirngadi Hospital, Medan, from January 1 to February 28, 1993. Blood gas analysis was done on blood obtained from umbilical artery. Based on 1st and 5th minutes Apgar scores, 40 (88.9%) and 21 babies (46.7%}, respectively, had asphyxia. Relation to acid-base balance was determined with the sensitivity of the 5th minute Apgar score in predicting acidotic states. It was found that Apgar score had sensitivity of 57.7% and specificity of 68.4% in predicting the acidotic states. Apgar score of > 7 was unable to. exclude the possible acidosis in 45% of cases (negative predictive value 54.1%). Gestational age had no influence on Apgar Scores. Apgar score was more sensitive to eliminate suspected acidosis in term neonates than in preterms. We recommend to perform umbilical arterial blood gas analysis to determine acidotic state in high risk newborn infants.


1989 ◽  
Vol 10 (04) ◽  
pp. 279-285 ◽  
Author(s):  
T. Yoshida ◽  
M. Udo ◽  
M. Chida ◽  
K. Makiguchi ◽  
M. Ichioka ◽  
...  

2015 ◽  
Vol 22 (4) ◽  
pp. 63-73
Author(s):  
Качур ◽  
S. Kachur ◽  
Долгих ◽  
V. Dolgikh

This work presents the effects of multimodal anesthesia with neuraxial blockade on the basic parameters of central hemodynamics in patients operated for lung tumors, revealed by method of terapolar rheovasography by Kubicek (systolic blood pressure, diastolic, average heart rate, ejection fraction, minute volume of blood circulation, cardiac index, oxygen delivery index, the index of the total peripheral vascular resistance), as well the effects on acid‐base balance of arterial blood in the immediate post‐operative period. The level of antinociceptive protection was assessed by visual analogue scale. Comparison of results of patients operated by means of multimodal anesthesia and the patients, operated in an inhalation intravenous anesthesia with artificial lung ventilation and peri‐operative analgesia by opioid analgesics has revealed that the hemodynamic profile of the first group of patients is characterized by stability of the basic parameters such as blood pressure and heart rate, the lack of a pronounced reduction of the ejection fraction and stroke volume of the heart, despite vasoplegia caused by epidural blockade. The level of partial oxygen tension of arterial blood was decreased in the early postoperative period, but it was in the normal limits and he was statistically significantly higher than in the comparison group that can help reduce the risk of post‐operative complications. Significantly lower level of pain indicates adequate antinociceptive protection of patients.


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