Ventilatory response of the diamondback water snake,Natrix rhombifera to hypoxia, hypercapnia and increased oxygen demand

1979 ◽  
Vol 129 (2) ◽  
pp. 105-110 ◽  
Author(s):  
Ronald K. Gratz
Keyword(s):  
Ventilatory Response ◽  
Oxygen Demand ◽  
Water Snake

Effect of bilateral vagotomy on the ventilatory responses of the water snake Nerodia sipedon

1984 ◽  
Vol 246 (2) ◽  
pp. R221-R227
Author(s):  
R. K. Gratz
Keyword(s):  
Heart Rate ◽  
Ventilatory Response ◽  
Pulmonary Ventilation ◽  
Nerodia Sipedon ◽  
Peripheral Chemoreceptor ◽  
Fourfold Increase ◽  
Co2 Partial Pressure ◽  
Water Snake ◽  
Bilateral Vagotomy ◽  
Breathing Room

The effects of bilateral vagotomy on pulmonary ventilation, O2 consumption, and heart rate were determined for the water snake, Nerodia sipedon, breathing room air at 15, 25, and 30 degrees C and breathing 5.2% CO2 in air at 25 degrees C. At all body temperatures, vagotomy resulted in a four- to sevenfold increase in tidal volume in snakes breathing room air. At the same time, ventilatory frequency decreased such that pulmonary ventilation was unchanged after vagotomy. Heart rate increased approximately 1.5 times after vagotomy, but O2 uptake was unchanged. The air convection requirement decreased similarly with increasing body temperature in both intact and vagotomized snakes. Arterial pH values were similar to those of intact snakes measured in a previous study and decreased by -0.013 U/degrees C. Since this occurs despite elimination of peripheral chemoreceptor input, it is suggested that the temperature compensation is a centrally controlled process. In intact snakes, breathing CO2 resulted in a fourfold increase in ventilation. Elimination of peripheral receptor input by vagotomy resulted in a loss of this ventilatory response to CO2 breathing. This means that peripheral receptors are required for a response to changes in arterial CO2 partial pressure and pH. Snakes thus differ from turtles and mammals in that central chemoreceptors alone are unable to produce the ventilatory response to inspired CO2.

scholarly journals Acute and chronic exposure to hypoxia alters ventilatory pattern but not minute ventilation of mice overexpressing erythropoietin

2007 ◽  
Vol 293 (4) ◽  
pp. R1702-R1710 ◽  
Author(s):  
Jorge Soliz ◽  
Christophe Soulage ◽  
Dirk M. Hermann ◽  
Max Gassmann
Keyword(s):  
Neural Control ◽  
Ventilatory Response ◽  
Minute Ventilation ◽  
Oxygen Demand ◽  
Respiratory Frequency ◽  
Dopamine Synthesis ◽  
Transgenic Mouse Line ◽  
Carotid Bodies ◽  
Acute And Chronic Exposure ◽  
The Impact

Apart from enhancing red blood cell production, erythropoietin (Epo) has been shown to modulate the ventilatory response to reduced oxygen supply. Both functions are crucial for the organism to cope with increased oxygen demand. In the present work, we analyzed the impact of Epo and the resulting excessive erythrocytosis in the neural control of normoxic and hypoxic ventilation. To this end, we used our transgenic mouse line (Tg6) that shows high levels of human Epo in brain and plasma, the latter leading to a hematocrit of ∼80%. Interestingly, while normoxic and hypoxic ventilation in Tg6 mice was similar to WT mice, Tg6 mice showed an increased respiratory frequency but a decreased tidal volume. Knowing that Epo modulates catecholaminergic activity, the altered catecholaminergic metabolism measured in brain stem suggested that the increased respiratory frequency in Tg6 mice was related to the overexpression of Epo in brain. In the periphery, higher response to hyperoxia (Dejours test), as well as reduced tyrosine hydroxylase activity in carotid bodies, revealed a higher chemosensitivity to oxygen in transgenic mice. Moreover, in line with the decreased activity of the rate-limiting enzyme for dopamine synthesis, the intraperitoneal injection of a highly specific peripheral ventilatory stimulant, domperidone, did not stimulate hypoxic ventilatory response in Tg6 mice. These results suggest that high Epo plasma levels modulate the carotid body's chemotransduction. All together, these findings are relevant for understanding the cross-talk between the ventilatory and erythropoietic systems exposed to hypoxia.

75 Oscillatory ventilation at rest coexisting with increased ventilatory response to exercise allow to identify heart failure patients with very poor outcome

2007 ◽  
Vol 6 (1) ◽  
pp. 15-15
Author(s):  
T WITKOWSKI ◽  
K NOWAK ◽  
A GRZESLO ◽  
E JANKOWSKA ◽  
J PETRUKKOWALCZYK ◽  
...  
Keyword(s):  
Heart Failure ◽  
Ventilatory Response ◽  
Heart Failure Patients ◽  
Oscillatory Ventilation ◽  
Poor Outcome ◽  
Response To Exercise

337 Nitric oxide exhalation correlates with ventilatory response to the exercise in patients with heart disease

2003 ◽  
Vol 2 (1) ◽  
pp. 63-64
Author(s):  
H ADACHI ◽  
S SAKURAI ◽  
T TOYAMA ◽  
H HOSHIZAKI ◽  
S OSHIMA ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Heart Disease ◽  
Ventilatory Response

Prothrombin-Activator (Thromboplastin) Generation in the Blood of Water Snake (Natrix piscator)

1981 ◽  
Vol 46 (04) ◽  
pp. 747-748
Author(s):  
V M Srivastava ◽  
B Dube ◽  
R K Dube ◽  
G P Agarwal
Keyword(s):  
Comparative Studies ◽  
One Stage ◽  
Water Snake ◽  
Generation Test ◽  
Mammalian System

SummaryThe generation of prothrombin-activator (thromboplastin) in water snake (Natrix piscator) is clearly delayed, Compared to a mammalian system, but the final activity is well comparable to that in man, when homologous sources of “phospholipid” (erythrocyte-lysate) and of substrate plasma are employed in one stage “thromboplastin generation test”. The use of heterologous source of either of the above reagents resulted in significantly longer clotting times; hence the need for homologous source of above reagents in the test is emphasized for comparative studies on animal haemostasis.

DECOLOURIZATION AND COD REMOVAL OF WASEWATER FROM ETHANOL PRODUCTION PROCESS FROM MOLASSES BY COAGULANTION USING INORGANIC ALUM

2010 ◽  
Vol 13 (3) ◽  
pp. 92-102
Author(s):  
Trung Duc Le
Keyword(s):  
Ethanol Production ◽  
Oxygen Demand ◽  
Cod Removal ◽  
Treated Wastewater ◽  
Treatment Processes ◽  
Physico Chemical ◽  
Biological Methods ◽  
Treatment Step ◽  
Main Material

The industrial production of ethanol by fermentation using molasses as main material that generates large quantity of wastewater. This wastewater contains high levels of colour and chemical oxygen demand (COD), that may causes serious environmental pollution. Most available treatment processes in Vietnam rely on biological methods, which often fail to treat waste water up to discharge standard. As always, it was reported that quality of treated wastewater could not meet Vietnameses discharge standard. So, it is necessary to improve the treatment efficiency of whole technological process and therefore, supplemental physico-chemical treatment step before biodegradation stage should be the appropriate choice. This study was carried out to assess the effect of coagulation process on decolourization and COD removal in molasses-based ethanol production wastewater using inorganic coaglutant under laboratory conditions. The experimental results showed that the reductions of COD and colour with the utilization of Al2(SO4)3 at pH 9.5 were 83% and 70%, respectively. Mixture FeSO4 – Al2(SO4)3 at pH 8.5 reduced 82% of colour and 70% of COD. With the addition of Polyacrylamide (PAM), the reduction efficiencies of colour, COD and turbidity by FeSO4 – Al2(SO4)3 were 87%, 73.1% and 94.1% correspondingly. It was indicated that PAM significantly reduced the turbidity of wastewater, however it virtually did not increase the efficiencies of colour and COD reduction. Furthermore, the coagulation processes using PAM usually produces a mount of sludge which is hard to be deposited.

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