scholarly journals THE PULMONARY ARTERIAL PRESSURE IN NORMAL ALBINO RATS AND THE EFFECT THEREON OF EPINEPHRINE

1934 ◽  
Vol 59 (2) ◽  
pp. 173-180 ◽  
Author(s):  
F. J. C. Smith ◽  
Granville A. Bennett

1. A satisfactory method for the direct determination of the pulmonary arterial pressure in rats is described. 2. The arithmetical mean of the blood pressure in the pulmonary artery in a series of thirty-four normal albino rats under nembutal anesthesia is 256 mm. H20 (18.8 mm. Hg). 3. Intravenous epinephrine causes an abrupt but briefly sustained rise in the pulmonary arterial pressure with a gradual return to normal.

1989 ◽  
Vol 76 (6) ◽  
pp. 589-594 ◽  
Author(s):  
Maurizio D. Guazzi ◽  
Marco Berti ◽  
Elisabetta Doria ◽  
Cesare Fiorentini ◽  
Claudia Galli ◽  
...  

1. In systemic hypertension the pulmonary vessels show an excessive tone at rest and hyper-react to adrenoceptor stimulation. Alterations in Ca2+ handling by the vascular smooth muscle cells seem to underlie these disorders. Alveolar hypoxia also constricts pulmonary arteries, increasing the intracellular Ca2+ availability for smooth muscle contraction. This suggests the hypothesis that hypoxic pulmonary vasoconstriction depends on similar biochemical disorders, and that the response to the hypoxic stimulus may be emphasized in high blood pressure. 2. In 21 hypertensive and 10 normotensive men, pulmonary arterial pressure and arteriolar resistance have been evaluated during air respiration and after 15 min of breathing 17, 15 and 12% oxygen in nitrogen. Curves relating changes in pulmonary arterial pressure and arteriolar resistance to the oxygen content of inspired gas had a similar configuration in the two populations, but in hypertension were steeper and significantly shifted to the left of those in normotension, reflecting a lower threshold and an enhanced vasoconstrictor reactivity. 3. This pattern was not related to differences in severity of the hypoxic stimulus, degree of hypocapnia and respiratory alkalosis induced by hypoxia, and plasma catecholamines. 4. The association of high blood pressure with enhanced pulmonary vasoreactivity to alveolar hypoxia could have clinical implications in patients who are chronically hypoxic and have systemic hypertension.


1964 ◽  
Vol 207 (6) ◽  
pp. 1314-1318 ◽  
Author(s):  
Benson R. Wilcox ◽  
W. Gerald Austen ◽  
Harvey W. Bender

The mechanism by which the pulmonary artery pressure rises in response to hypoxia has never been clearly demonstrated. This problem was reinvestigated in experiments utilizing separate pulmonary and systemic perfusion systems. These vascular beds were perfused in such a fashion that a change in pulmonary artery pressure could only result from changes in vasomotor tone. Alveolar-pulmonary vein hypoxia was usually associated with a slight fall in pulmonary artery pressure. Systemic hypoxia resulted in elevation of pulmonary arterial pressure in 10 of the 12 animals tested with a constant-flow and constant-pulmonary venous pressure. In addition, all animals with systemic desaturation showed an increased venous return. When the "cardiac output" (pump output) was increased to match this return, the elevation in pulmonary artery pressure increased. It was concluded that the pulmonary arterial pressure elevation seen with hypoxia is the result of active pulmonary vasoconstriction coupled with an increased pulmonary blood flow.


1996 ◽  
Vol 80 (2) ◽  
pp. 711-712 ◽  
Author(s):  
B. Agroyannis ◽  
A. Dalamangas ◽  
H. Tzanatos ◽  
C. Fourtounas ◽  
I. Kopelias ◽  
...  

Isolated rabbit lungs were perfused with washed and resuspended human red blood cells (RBCs) in the presence of drugs known to change the shape and deformability of RBCs. With sodium salicylate (0.5-2 g/l), which causes echinocytosis and increases RBC deformability, lung diffusing capacity for O2 (DLO2) increased by 21%. When chlorpromazine, which induces stomatocytosis and stiffens RBCs, was given (50 mg/l), DLO2 decreased by 18% under chlorpromazine. Comparative experiments with hemoglobin solutions did not reveal any effect of those two drugs either on DLO2 or on pulmonary arterial pressure, which indicates that the effects of sodium salicylate and chlorpromazine were due to changes in RBC shape and deformability. It is concluded that RBC shape and deformability affect pulmonary artery pressure and oxygen diffusing capacity, which may have an influence on oxygen transfer to tissue and hence be of clinical relevance.


1988 ◽  
Vol 64 (5) ◽  
pp. 1823-1828 ◽  
Author(s):  
A. T. Scardella ◽  
J. A. Neubauer ◽  
N. H. Edelman ◽  
T. V. Santiago

The effects of endogenously generated opioids on distribution of pulmonary perfusion (as assessed by radiolabeled microspheres) and overall gas exchange in acute acid-induced lung injury were studied. In 14 anesthesized dogs, sufficient acid was given to one lung to double shunt fraction (Qs/Qt) from 14.2 +/- 0.8 to 32.4 +/- 2.6% (SE). This resulted in a significant decrease in Po2 from 495 +/- 9 to 136 +/- 21 Torr, cardiac output from 2.47 +/- 0.27 to 1.46 +/- 0.15 1/min, and blood pressure from 139 +/- 3 to 116 +/- 5 mmHg and a significant rise in pulmonary arterial pressure from 9.6 +/- 0.8 to 14.9 +/- 0.8 mmHg. After acid instillation, microsphere distribution to the injured lung segments decreased to 50% of the base-line value. At the same time, microsphere distribution in the normal segments increased to 160% of base line. In 7 of the 14 dogs the effects of naloxone (1 mg/kg) given after lung injury were compared with the other 7 animals that were given saline. Naloxone administration caused a significant redistribution of regional pulmonary perfusion such that microsphere distribution in the injured lung segments increased by a factor of 2 at 35 min compared with the animals given saline. Consistent with this finding, Qs/Qt in the naloxone group increased to 34.7 +/- 5.0% at 35 min, whereas that of the saline group decreased to 28.2 +/- 2.5%. The difference between the two groups was significant at 35 min. These changes occurred without further alterations in cardiac output, pulmonary arterial pressure, or systemic blood pressure in either group.(ABSTRACT TRUNCATED AT 250 WORDS)


1929 ◽  
Vol 49 (1) ◽  
pp. 21-31 ◽  
Author(s):  
Stephen Went ◽  
Cecil K. Drinker

1. Sheep serum in doses below 0.3 cc. intravenously produces no pulmonary vasoconstriction in the guinea pig. Guinea pigs have consequently been sensitized with this substance and anaphylactic shock produced by doses of O.1 and 0.2 cc. 2. Pressure in the pulmonary artery has been measured by the method of Drinker and Went (2) and recorded photographically in a new and convenient manner. 3. At a very early stage in anaphylactic shock the pulmonary arterial pressure falls markedly and this fall seems to precede the appearance of bronchiolar obstruction. 4. The fall in pulmonary blood pressure in anaphylactic shock is in marked contrast to the rise in pressure resulting from intravenous injection of toxic foreign protein, such as horse serum.


Open Medicine ◽  
2008 ◽  
Vol 3 (4) ◽  
pp. 482-486
Author(s):  
Saeed Abdelwhab ◽  
Khaled. Dessoukey ◽  
Gamal Lotfy ◽  
Ashraf Alsaeed ◽  
Hesham Anwar

AbstractThe aim of the study was to determine the mean pulmonary pressure in adult with hypertrophic tonsils and adenoids and to clarify whether tonsillectomy and adenoidectomy has any effect on mean pulmonary arterial pressure of these adult. The study was carried out on 50 patients with diagnosis of upper airway obstruction resulting from hypertrophied tonsils and adenoids (group1). 25 adults were assigned as control with similar age and sex distribution (group2). For study subjects Routine general Examinations, BMI, ECG, Chest X ray, Arterial blood gases and Echocardiography were done. Mean pulmonary arterial pressure was measured by using Doppler Echocardiography preoperatively and mean 3–4 months postoperatively in all subjects. Elevated PAP (pulmonary artery pressure) was found in 15 patients (30%) in group 1 preoperatively. Mean PAP was 28.34 ±5.11 mmHg preoperative in group 1 and 19.84 ± 5.0 mmHg in group 2 (p <0.001). PAP decrease to 22.38 ±4.28 mmHg postoperatively in group 1 (p <0.001). Arterial oxygen saturation (spo2%) increase from 93.5 ± 1.9% preoperatively to 95.3 ± 1.3% post operatively (p < 0.001). percent reduction of PAP postoperatively correlates to age (t=−2.3, p= 0.02), preoperative PAP (p =0.01) but no correlation was found with BMI. In conclusions, this Study showed that obstructed adenoid and hypertrophy of tonsils causes higher mean pulmonary artery pressure in adult & revealed that tonsil& adenoid is effective therapeutic measure in such patients. With early intervention is necessary to avoid progressive cardiopulmonary disease.


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