Comparative Biochemistry and Physiology Part A: Physiology, 1972
... We believe, therefore, that our data should be applicable to eggs near hatching which have in... more ... We believe, therefore, that our data should be applicable to eggs near hatching which have incubated under natural conditions. Despite the twofold difference, the permeability of the turtle and chick egg shell is of the same order of magnitude. ...
The ventilatory response of green turtles (Chelonia mydas) to inspired CO2 was tested. Both immat... more The ventilatory response of green turtles (Chelonia mydas) to inspired CO2 was tested. Both immature (0.9--1.35 kg) and adult (59--130 kg) animals responded with increased ventilation (VE) that was primarily (immature) or exclusively (adult) due to increased respiratory frequency. The VE of the immature turtles while breathing air increased with temperatures between 15 and 35 degrees C with a Q10 of 1.95, but the peak VE of these turtles while breathing 4.5% CO2 in air was not significantly different at 15, 25 or 35 degrees C. VE increased irregularly with time throughout an hour of CO2 breathing in both groups, although several of the adult animals exhibited a first-breath response to CO2 and all animals increased VE within 5 min after the onset of CO2 breathing. The VE of an immature turtle at 35 degrees C increased with graded increases in CO2 up to 6%, but at 15 and 25 degrees C VE increased only up to 4.5% and decreased with 6% CO2. The results are discussed in terms of possibl...
Journal of applied physiology (Bethesda, Md. : 1985), 2001
The PO(2)-dependent binding of chloride to Hb decreases the Cl(-) concentration of the red blood ... more The PO(2)-dependent binding of chloride to Hb decreases the Cl(-) concentration of the red blood cell (RBC) intracellular fluid in venous blood to approximately 1-3 mmol/l less than that in arterial blood. This change is physiologically important because 1) Cl(-) is a negative heterotropic allosteric effector of Hb that competes for binding sites with 2,3-bisphosphoglycerate and CO(2) and decreases oxyhemoglobin affinity in several species; 2) it may help reconcile several longstanding problems with measured values of the Donnan ratios for Cl(-), HCO, and H(+) across the RBC membrane that are used to calculate total CO(2) carriage, ion flux rates, and membrane potentials; 3) it is a factor in the change in the dissociation constant for the combined nonvolatile weak acids of Hb associated with the Haldane effect; and 4) it diminishes the decrease in strong ion difference in the RBC intracellular fluid that would otherwise occur from the chloride shift and prevent the known increase o...
We tested the hypothesis that CO2 and heat have different effects on the ventilatory pattern of g... more We tested the hypothesis that CO2 and heat have different effects on the ventilatory pattern of grasshoppers Melanoplus differentialis. Eight grasshoppers were sealed between rostral (inspiratory) and caudal (expiratory) spiracles in separated, airtight, chambers and pressure changes were measured. Normal breathing patterns decreased pressure in the rostral chamber and increased pressure in the caudal chamber (i.e. unidirectional pumping rostral to caudal). Insects exposed to ventilatory stimulation by CO2 or heat significantly increased pumping frequency from 26+/-2 (+/-S.E.M.) at 0% CO2 to 54+/-6 breaths/min at 8% CO2 (at 30 degrees C), and from 27+/-3 at 30 degrees C to 44+/-4 breaths/min at 45 degrees C. Unidirectional pumping failed to change with increased CO2 concentration and increased significantly with heat exposure. Thus, while CO2 only increased pumping frequency, heat increased pumping frequency and unidirectional pumping.
Ventilation of green turtles (Chelonia mydas) was affected by the position in which the animal wa... more Ventilation of green turtles (Chelonia mydas) was affected by the position in which the animal was placed: supine animals breathed slowly 0.07 breaths/min) and deeply (8.0 L/breath); prone animals breathed more rapidly (0.43 breaths/min) and more shallowly (3.5 L/breath). From the respiratory exchange ratio and other indicators it appears that green turtles hyperventilate during exercise and hypoventilate during recovery. O2 consumption of the resting sea turtle (0.024 L-kg-1-h-1) is similar to that of other large turtles. Maximal O2 consumption (0.25L-kg-1-h-1) is greater than that of other large turtles. Minimal O2 consumption scaled in proportion to the -0.17 power of the body mass of green turtles over the range of 0.030 to 141.5 kg. The maximal O2 consumption scaled in proportion to the -0.06 power of body mass for the same range of body masses.
Some species of cranes have extensive coiling of their trachea that substantially increases their... more Some species of cranes have extensive coiling of their trachea that substantially increases their anatomical dead space. We subjected individuals of four species of cranes (Anthropoides virgo, Balearica regulorum, Grus grus and Grus japonensis) to acute heat stress to investigate the effectiveness of this trait as a thermoregulatory adaptation. We measured cloacal temperature, respiratory flow and frequency and arterial pH during normothermic breathing and thermal panting. Extra tracheal length appears to be a helpful but nonessential adaptation to prevent cranes from becoming alkalotic while panting. Cranes in our study had relatively lower panting frequencies and greater tidal volumes than have been reported for other birds subjected to heat stress. Tracheal coiling is probably more important to vocalization than to respiration or thermoregulation.
ABSTRACT 1.1. The skin, rather than the respiratory tract, was the major avenue for evaporative w... more ABSTRACT 1.1. The skin, rather than the respiratory tract, was the major avenue for evaporative water loss in the two species of snakes examined.2.2. The total evaporation of the brown water snake (Natrix taxispilota) was 3·3 times greater than that of the desert-dwelling Sonora gopher snake (Pituophis catenifer affinis).3.3. The pulmonary component of evaporation was nearly the same in the two species, hence the cutaneous component accounted for the difference in total evaporation.4.4. These results are in accord with findings in other reptiles, which likewise show a correlation of reduced evaporative water loss to the aridity of their environment.
... BY JOHN F. ANDERSON,' HERMANN RAHN,2 AND HENRY D. PRANGE3 ... Smith and Pace (1971) revi... more ... BY JOHN F. ANDERSON,' HERMANN RAHN,2 AND HENRY D. PRANGE3 ... Smith and Pace (1971) reviewed the extensive Japanese literature (Omura, 1950; Nishiwaki, 1950, 1959; Nishiwaki and Oye, 1951; Fujino, 1955) relating to the organ and body mass of whales. ...
River otters (Lontra canadensis) are highly active, semi-aquatic mammals indigenous to a range of... more River otters (Lontra canadensis) are highly active, semi-aquatic mammals indigenous to a range of elevations and represent an appropriate model for assessing the physiological responses to diving at altitude. In this study, we performed blood gas analyses and compared blood chemistry of river otters from a high-elevation (2357 m) population at Yellowstone Lake with a sea-level population along the Pacific coast. Comparisons of oxygen dissociation curves (ODC) revealed no significant difference in hemoglobin-oxygen (Hb-O(2)) binding affinity between the two populations - potentially because of demands for tissue oxygenation. Instead, high-elevation otters had greater Hb concentrations (18.7 g dl(-1)) than sea-level otters (15.6 g dl(-1)). Yellowstone otters displayed higher levels of the vasodilator nitric oxide (NO), and half the concentration of the serum protein albumin, possibly to compensate for increased blood viscosity. Despite compensation in several hematological and serological parameters, theoretical aerobic dive limits (ADL) were similar between high-elevation and sea-level otters because of the lower availability of O(2) at altitude. Our results suggest that recent disruptions to the Yellowstone Lake food web could be detrimental to otters because at this high elevation, constraints on diving may limit their ability to switch to prey in a deep-water environment.
... Bloomington, Indiana 47401; Department of Zoology, University of Florida, Gainesville, Florid... more ... Bloomington, Indiana 47401; Department of Zoology, University of Florida, Gainesville, Florida 32611; Department of Physiology, Schools of Medicine and Dentistry ... Thus the birds may have achieved an internal redistribution of skeletal mass but not an overall relative reduction. ...
The chloride shift is the movement of Cl(-) from the plasma into erythrocytes as blood moves from... more The chloride shift is the movement of Cl(-) from the plasma into erythrocytes as blood moves from the arterial to the venous end of systemic capillaries. The traditional explanation for the chloride shift emphasizes the causative roles of the rise in Pco(2) and the exclusive presence of carbonic anhydrase within the red blood cell. The purpose of this article is, first, to reexamine two aspects of the chloride shift that we feel are traditionally underemphasized. They are the role of hemoglobin in causing the chloride shift and the affect of the chloride shift on the acid-base status of the blood. Second, we wish to reconcile more recent work with the traditional understanding of the chloride shift. The chloride shift has never been modeled from the perspective of the Stewart strong ion approach. Similarly, the traditional understanding has generally treated Cl(-) as a passive participant in the chloride shift whose role was simply to replace the lost negative charge of the outward moving HCO-3. More recent work has suggested that the ingoing Cl(-) is important for both O(2) unloading and acid-base balance of the blood. We conclude this article with a model of the chloride shift that uses the Stewart approach and, though harmonious with the traditional understanding, highlights the importance of hemoglobin and Cl(-) in the chloride shift.
... CORY R. ETCHBERGER*, MICHAEL A. EWERT, JOHN B. PHILLIPS, CRAIG E. NELSON Department of Biolog... more ... CORY R. ETCHBERGER*, MICHAEL A. EWERT, JOHN B. PHILLIPS, CRAIG E. NELSON Department of Biology, Indiana University, Bloomington, IN ... For the 2 gas studies, the incubation boxes were placed in treatment chambers through which the appropriate gas mixture ...
Comparative Biochemistry and Physiology Part A: Physiology, 1972
... We believe, therefore, that our data should be applicable to eggs near hatching which have in... more ... We believe, therefore, that our data should be applicable to eggs near hatching which have incubated under natural conditions. Despite the twofold difference, the permeability of the turtle and chick egg shell is of the same order of magnitude. ...
The ventilatory response of green turtles (Chelonia mydas) to inspired CO2 was tested. Both immat... more The ventilatory response of green turtles (Chelonia mydas) to inspired CO2 was tested. Both immature (0.9--1.35 kg) and adult (59--130 kg) animals responded with increased ventilation (VE) that was primarily (immature) or exclusively (adult) due to increased respiratory frequency. The VE of the immature turtles while breathing air increased with temperatures between 15 and 35 degrees C with a Q10 of 1.95, but the peak VE of these turtles while breathing 4.5% CO2 in air was not significantly different at 15, 25 or 35 degrees C. VE increased irregularly with time throughout an hour of CO2 breathing in both groups, although several of the adult animals exhibited a first-breath response to CO2 and all animals increased VE within 5 min after the onset of CO2 breathing. The VE of an immature turtle at 35 degrees C increased with graded increases in CO2 up to 6%, but at 15 and 25 degrees C VE increased only up to 4.5% and decreased with 6% CO2. The results are discussed in terms of possibl...
Journal of applied physiology (Bethesda, Md. : 1985), 2001
The PO(2)-dependent binding of chloride to Hb decreases the Cl(-) concentration of the red blood ... more The PO(2)-dependent binding of chloride to Hb decreases the Cl(-) concentration of the red blood cell (RBC) intracellular fluid in venous blood to approximately 1-3 mmol/l less than that in arterial blood. This change is physiologically important because 1) Cl(-) is a negative heterotropic allosteric effector of Hb that competes for binding sites with 2,3-bisphosphoglycerate and CO(2) and decreases oxyhemoglobin affinity in several species; 2) it may help reconcile several longstanding problems with measured values of the Donnan ratios for Cl(-), HCO, and H(+) across the RBC membrane that are used to calculate total CO(2) carriage, ion flux rates, and membrane potentials; 3) it is a factor in the change in the dissociation constant for the combined nonvolatile weak acids of Hb associated with the Haldane effect; and 4) it diminishes the decrease in strong ion difference in the RBC intracellular fluid that would otherwise occur from the chloride shift and prevent the known increase o...
We tested the hypothesis that CO2 and heat have different effects on the ventilatory pattern of g... more We tested the hypothesis that CO2 and heat have different effects on the ventilatory pattern of grasshoppers Melanoplus differentialis. Eight grasshoppers were sealed between rostral (inspiratory) and caudal (expiratory) spiracles in separated, airtight, chambers and pressure changes were measured. Normal breathing patterns decreased pressure in the rostral chamber and increased pressure in the caudal chamber (i.e. unidirectional pumping rostral to caudal). Insects exposed to ventilatory stimulation by CO2 or heat significantly increased pumping frequency from 26+/-2 (+/-S.E.M.) at 0% CO2 to 54+/-6 breaths/min at 8% CO2 (at 30 degrees C), and from 27+/-3 at 30 degrees C to 44+/-4 breaths/min at 45 degrees C. Unidirectional pumping failed to change with increased CO2 concentration and increased significantly with heat exposure. Thus, while CO2 only increased pumping frequency, heat increased pumping frequency and unidirectional pumping.
Ventilation of green turtles (Chelonia mydas) was affected by the position in which the animal wa... more Ventilation of green turtles (Chelonia mydas) was affected by the position in which the animal was placed: supine animals breathed slowly 0.07 breaths/min) and deeply (8.0 L/breath); prone animals breathed more rapidly (0.43 breaths/min) and more shallowly (3.5 L/breath). From the respiratory exchange ratio and other indicators it appears that green turtles hyperventilate during exercise and hypoventilate during recovery. O2 consumption of the resting sea turtle (0.024 L-kg-1-h-1) is similar to that of other large turtles. Maximal O2 consumption (0.25L-kg-1-h-1) is greater than that of other large turtles. Minimal O2 consumption scaled in proportion to the -0.17 power of the body mass of green turtles over the range of 0.030 to 141.5 kg. The maximal O2 consumption scaled in proportion to the -0.06 power of body mass for the same range of body masses.
Some species of cranes have extensive coiling of their trachea that substantially increases their... more Some species of cranes have extensive coiling of their trachea that substantially increases their anatomical dead space. We subjected individuals of four species of cranes (Anthropoides virgo, Balearica regulorum, Grus grus and Grus japonensis) to acute heat stress to investigate the effectiveness of this trait as a thermoregulatory adaptation. We measured cloacal temperature, respiratory flow and frequency and arterial pH during normothermic breathing and thermal panting. Extra tracheal length appears to be a helpful but nonessential adaptation to prevent cranes from becoming alkalotic while panting. Cranes in our study had relatively lower panting frequencies and greater tidal volumes than have been reported for other birds subjected to heat stress. Tracheal coiling is probably more important to vocalization than to respiration or thermoregulation.
ABSTRACT 1.1. The skin, rather than the respiratory tract, was the major avenue for evaporative w... more ABSTRACT 1.1. The skin, rather than the respiratory tract, was the major avenue for evaporative water loss in the two species of snakes examined.2.2. The total evaporation of the brown water snake (Natrix taxispilota) was 3·3 times greater than that of the desert-dwelling Sonora gopher snake (Pituophis catenifer affinis).3.3. The pulmonary component of evaporation was nearly the same in the two species, hence the cutaneous component accounted for the difference in total evaporation.4.4. These results are in accord with findings in other reptiles, which likewise show a correlation of reduced evaporative water loss to the aridity of their environment.
... BY JOHN F. ANDERSON,' HERMANN RAHN,2 AND HENRY D. PRANGE3 ... Smith and Pace (1971) revi... more ... BY JOHN F. ANDERSON,' HERMANN RAHN,2 AND HENRY D. PRANGE3 ... Smith and Pace (1971) reviewed the extensive Japanese literature (Omura, 1950; Nishiwaki, 1950, 1959; Nishiwaki and Oye, 1951; Fujino, 1955) relating to the organ and body mass of whales. ...
River otters (Lontra canadensis) are highly active, semi-aquatic mammals indigenous to a range of... more River otters (Lontra canadensis) are highly active, semi-aquatic mammals indigenous to a range of elevations and represent an appropriate model for assessing the physiological responses to diving at altitude. In this study, we performed blood gas analyses and compared blood chemistry of river otters from a high-elevation (2357 m) population at Yellowstone Lake with a sea-level population along the Pacific coast. Comparisons of oxygen dissociation curves (ODC) revealed no significant difference in hemoglobin-oxygen (Hb-O(2)) binding affinity between the two populations - potentially because of demands for tissue oxygenation. Instead, high-elevation otters had greater Hb concentrations (18.7 g dl(-1)) than sea-level otters (15.6 g dl(-1)). Yellowstone otters displayed higher levels of the vasodilator nitric oxide (NO), and half the concentration of the serum protein albumin, possibly to compensate for increased blood viscosity. Despite compensation in several hematological and serological parameters, theoretical aerobic dive limits (ADL) were similar between high-elevation and sea-level otters because of the lower availability of O(2) at altitude. Our results suggest that recent disruptions to the Yellowstone Lake food web could be detrimental to otters because at this high elevation, constraints on diving may limit their ability to switch to prey in a deep-water environment.
... Bloomington, Indiana 47401; Department of Zoology, University of Florida, Gainesville, Florid... more ... Bloomington, Indiana 47401; Department of Zoology, University of Florida, Gainesville, Florida 32611; Department of Physiology, Schools of Medicine and Dentistry ... Thus the birds may have achieved an internal redistribution of skeletal mass but not an overall relative reduction. ...
The chloride shift is the movement of Cl(-) from the plasma into erythrocytes as blood moves from... more The chloride shift is the movement of Cl(-) from the plasma into erythrocytes as blood moves from the arterial to the venous end of systemic capillaries. The traditional explanation for the chloride shift emphasizes the causative roles of the rise in Pco(2) and the exclusive presence of carbonic anhydrase within the red blood cell. The purpose of this article is, first, to reexamine two aspects of the chloride shift that we feel are traditionally underemphasized. They are the role of hemoglobin in causing the chloride shift and the affect of the chloride shift on the acid-base status of the blood. Second, we wish to reconcile more recent work with the traditional understanding of the chloride shift. The chloride shift has never been modeled from the perspective of the Stewart strong ion approach. Similarly, the traditional understanding has generally treated Cl(-) as a passive participant in the chloride shift whose role was simply to replace the lost negative charge of the outward moving HCO-3. More recent work has suggested that the ingoing Cl(-) is important for both O(2) unloading and acid-base balance of the blood. We conclude this article with a model of the chloride shift that uses the Stewart approach and, though harmonious with the traditional understanding, highlights the importance of hemoglobin and Cl(-) in the chloride shift.
... CORY R. ETCHBERGER*, MICHAEL A. EWERT, JOHN B. PHILLIPS, CRAIG E. NELSON Department of Biolog... more ... CORY R. ETCHBERGER*, MICHAEL A. EWERT, JOHN B. PHILLIPS, CRAIG E. NELSON Department of Biology, Indiana University, Bloomington, IN ... For the 2 gas studies, the incubation boxes were placed in treatment chambers through which the appropriate gas mixture ...
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