scholarly journals Carbon dioxide and bicarbonate accumulation in caiman erythrocytes during diving

2021 ◽  
Author(s):  
Naim M. Bautista ◽  
Christian Damsgaard ◽  
Angela Fago ◽  
Tobias Wang
Keyword(s):  
Carbon Dioxide ◽  
Functional Implication

The ability of crocodilian haemoglobins to bind HCO3− has been appreciated for more than half a century, but the functional implication of this is exceptional mechanism has not previously been assessed in vivo. Therefore, the goal of the present study was to address the hypothesis that CO2 primarily binds to Hb, rather than being accumulated in plasma as in other vertebrates, during diving in caimans. Here, we demonstrate that CO2 primarily accumulates within the erythrocyte during diving and that most of the accumulated CO2 is bound to haemoglobin. Furthermore, we show that this HCO3−-binding is tightly associated with the progressive blood deoxygenation during diving, therefore, crocodilians differ from the classic vertebrate pattern, where HCO3− accumulates in the plasma upon excretion from the erythrocytes by the Cl−-HCO3−-exchanger.

scholarly journals Oxygen and Carbon Dioxide Transport Characteristics of the Blood of the Nile Monitor Lizard (Varanus Niloticus)

1987 ◽  
Vol 130 (1) ◽  
pp. 27-38
Author(s):  
JAMES W. HICKS ◽  
ATSUSHI ISHIMATSU ◽  
NORBERT HEISLER
Keyword(s):  
Carbon Dioxide ◽  
Haemoglobin Concentration ◽  
Oxygen Affinity ◽  
Total Blood ◽  
Carbon Dioxide Transport ◽  
Monitor Lizard ◽  
The Right ◽  
Dissociation Curves

Oxygen and carbon dioxide dissociation curves were constructed for the blood of the Nile monitor lizard, Varanus niloticus, acclimated for 12h at 25 and 35°C. The oxygen affinity of Varanus blood was low when Pco2 w a s in the range of in vivo values (25°C: P50 = 34.3 at PCOCO2 = 21 mmHg; 35°C: P50 = 46.2 mmHg at PCOCO2 = 35 mmHg; 1 mmHg = 133.3 Pa), and the oxygen dissociation curves were highly sigmoidal (Hill's n = 2.97 at 25°C and 3.40 at 35°C). The position of the O2 curves was relatively insensitive to temperature change with an apparent enthalpy of oxygenation (ΔH) of −9.2kJ mol−1. The carbon dioxide dissociation curves were shifted to the right with increasing temperature by decreasing total CCOCO2 at fixed PCOCO2, whereas the state of oxygenation had little effect on total blood CO2 content. The in vitro buffer value of true plasma (Δ[HCO3−]pl/-ΔpHpl) rose from 12.0 mequiv pH−1−1 at 25°C to 17.5 mequiv pH−11−1 at 35°C, reflecting a reversible increase of about 30% in haemoglobin concentration and haematocrit levels during resting conditions in vivo.

Carbon dioxide inhalation causes pulmonary inflammation

2009 ◽  
Vol 296 (4) ◽  
pp. L657-L665 ◽  
Author(s):  
Mohammad Abolhassani ◽  
Adeline Guais ◽  
Philippe Chaumet-Riffaud ◽  
Annie J. Sasco ◽  
Laurent Schwartz
Keyword(s):  
Carbon Dioxide ◽  
Nuclear Translocation ◽  
Rnase Protection Assay ◽  
Airway Hyperreactivity ◽  
Cellular Respiration ◽  
Rnase Protection ◽  
Monocyte Chemoattractant Protein 1 ◽  
Enhanced Production

The aim of this study was to assess whether one of the most common poisons of cellular respiration, i.e., carbon dioxide, is proinflammatory. CO2 is naturally present in the atmosphere at the level of 0.038% and involved in numerous cellular biochemical reactions. We analyzed in vitro the inflammation response induced by exposure to CO2 for 48 h (0–20% with a constant O2 concentration of 21%). In vivo mice were submitted to increasing concentrations of CO2 (0, 5, 10, and 15% with a constant O2 concentration of 21%) for 1 h. The exposure to concentrations above 5% of CO2 resulted in the increased transcription (RNase protection assay) and secretion (ELISA) of proinflammatory cytokines [macrophage inflammatory protein-1α (MIP-1α), MIP-1β, MIP-2, IL-8, IL-6, monocyte chemoattractant protein-1, and regulated upon activation, normal T cell expressed, and, presumably, secreted (RANTES)] by epithelial cell lines HT-29 or A549 and primary pulmonary cells retrieved from the exposed mice. Lung inflammation was also demonstrated in vivo by mucin 5AC-enhanced production and airway hyperreactivity induction. This response was mostly mediated by the nuclear translocation of p65 NF-κB, itself a consequence of protein phosphatase 2A (PP2A) activation. Short inhibiting RNAs (siRNAs) targeted toward PP2Ac reversed the effect of carbon dioxide, i.e., disrupted the NF-κB activation and the proinflammatory cytokine secretion. In conclusion, this study strongly suggests that exposure to carbon dioxide may be more toxic than previously thought. This may be relevant for carcinogenic effects of combustion products.

scholarly journals THE EFFECT OF EXCESS VITAMIN A ON THE EMBRYONIC RAT OESOPHAGUS IN CULTURE

1963 ◽  
Vol 118 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Ilse Lasnitzki
Keyword(s):  
Carbon Dioxide ◽  
Vitamin A ◽  
Organ Culture ◽  
Normal Medium ◽  
Adequate Supply ◽  
Stages Of Growth

The effect of excess vitamin A on the oesophageal epithelium of late foetal rats has been studied in organ culture. In explants kept in normal medium the epithelium is, at first, higher and the keratinisation increased as compared with the development of the organ in vivo. At the later stages of growth, the acceleration of keratinisation leads to an extreme thinning of the epithelium. Excess vitamin A completely inhibits keratinisation and induces a transformation of the cells lining the oesophageal lumen into mucin-secreting elements. In vitamin A-treated cultures the epithelium remains high throughout the whole period of cultivation. The amount of secretory matter and the height of the epithelium seem to depend on an adequate supply of oxygen and carbon dioxide to the cells.

In Vivo Visualization of Intracardiac Structures With Gaseous Carbon Dioxide

1956 ◽  
Vol 186 (2) ◽  
pp. 325-334 ◽  
Author(s):  
M. J. Oppenheimer ◽  
T. M. Durant ◽  
H. M. Stauffer ◽  
G. H. Stewart ◽  
P. R. Lynch ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Body Position ◽  
Left Heart ◽  
Mortality And Morbidity ◽  
X Ray ◽  
Carbon Dioxide Gas ◽  
Great Vessels ◽  
Gaseous Carbon Dioxide ◽  
The Right

Carbon dioxide gas was injected a) intravenously, b) into the left heart, c) into the peripheral end of the carotid artery. Resulting cardiovascular and respiratory changes were observed by cinefluorography and by measurements of pressure pulses in various locations. Blood and respiratory gas changes were also observed. All changes were minimal (seconds duration) when the gas was introduced on the right or left side of the circulation. Injection into the peripheral carotid produced no untoward effects. The gas gave good visualization of valves and great vessels. Body position was not an important factor in mortality and morbidity when carbon dioxide was the gas used for contrast visualization by a cinefluorography x-ray technique. Carbon dioxide is a safe contrast medium to use for in vivo study of intracardiac structures. The gas has been used successfully by intravenous injection in human cases.

Carbon Dioxide Fixation by Rat Heart Muscle in Vivo

1953 ◽  
Vol 173 (2) ◽  
pp. 335-336
Author(s):  
H. Eugene Hall ◽  
Edward W. Hawthorne ◽  
Lawrence M. Marshall
Keyword(s):  
Carbon Dioxide ◽  
Heart Muscle ◽  
Rat Heart ◽  
Carbon Dioxide Fixation

scholarly journals Chemical Composition of Celandine (Chelidonium majus L.) Extract and its Effects on Botrytis tulipae (Lib.) Lind Fungus and the Tulip

2013 ◽  
Vol 41 (2) ◽  
pp. 414 ◽  
Author(s):  
Marcel PARVU ◽  
Laurian VLASE ◽  
Laszlo FODORPATAKI ◽  
Ovidiu PARVU ◽  
Oana ROSCA-CASIAN ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Gas Exchange ◽  
Plant Extract ◽  
Transpiration Rate ◽  
Photosynthetic Apparatus ◽  
Chelidonium Majus ◽  
Gas Exchange Parameters ◽  
Nutritive Medium ◽  
Exchange Parameters

In this study, the content of chelidonine and berberine alkaloids, and sterols and phenols in the Chelidonium majus plant extract were analyzed. Subsequently, the effects of the extract on the germination and growth of Botrytis tulipae fungus on nutritive medium were compared to the effects of fluconazole. The plant extract was used at the minimum inhibitory concentration on B. tulipae developed in tulip leaves and the in vivo effects were investigated. The influence of different concentrations of C. majus extract on the physiological processes of the tulip (gas exchange parameters, photosynthetic light use efficiency, and induced chlorophyll fluorescence) were also tested to assess the applicability of the extract for the protection of ornamental plants against fungal infection. Our results demonstrated that 2% celandine extract does not significantly change the gas exchange parameters (transpiration rate, carbon dioxide uptake, and stomatal conductivity) of leaves exposed for 2 h, and does not interfere with the photochemical processes in the leaves. However, in higher concentrations, it increases the transpiration rate and net carbon dioxide influx. At concentrations of 15% and 20%, the extract lowers the potential quantum yield efficiency of photosystem II and the vitality index of the photosynthetic apparatus. Therefore we recommend the use of lower concentrations (≤6%) of celandine extract for the biological protection of tulips against gray mold.

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