Release of neuroendocrine products in the pulmonary circulation during intermittent hypoxia in isolated rat lung

Adenosine, a nucleoside and potent vasodilator, has been found to be taken up by the lung and converted by deamination into inosine and hypoxanthine. In a single circulation through an isolated rat lung, 69.3 +/- 3.3% of infused [14C]adenosine (10 microM) was removed from the circulation. Uptake of [14C]adenosine remained unchanged when deamination of adenosine was inhibited by 8-azaguanine or coformycin. In a single passage of adenosine through the pulmonary artery, very little of the deaminated products appeared in the pulmonary circulation, but when adenosine was recirculated through the pulmonary circulation inosine and hypoxanthine appeared in the venous effluent. These adenosine metabolites were also taken up by the lung. A major portion of the circulating adenosine was transported into the lung, where it was used to synthesize adenine nucleotides. Inhibition of adenosine kinase by iodotubercidin resulted in reduced formation of ATP and ADP. Uptake of adenosine by the lung was saturable on a concentration gradient and was a passive process because it was not affected by the absence of glucose or the presence of ouabain. Km and Vmax for adenosine transport were 0.227 mM and 4.6 mumol.min-1.g lung-1, respectively. Adenosine transport was inhibited by adenosine analogues, and the inhibitions were found to be competitive in nature. These results suggest that a specific and rate-limiting transport system exists in the lung for adenosine.

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Pulmonary preservation effect of nitroglycerine in isolated rat lung reperfusion model

Transplantation Proceedings ◽

10.1016/j.transproceed.2004.06.045 ◽

2004 ◽

Vol 36 (7) ◽

pp. 1933-1935 ◽

Cited By ~ 3

Author(s):

S. Jheon ◽

Y.M. Lee ◽

S.W. Sung ◽

J.H. Choh ◽

K.Y. Kwon ◽

...

Keyword(s):

Rat Lung ◽

Isolated Rat Lung ◽

Isolated Rat

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Effect of urodilatin on platelet-activating factor-induced bronchoconstriction, vasoconstriction and edema formation in isolated rat lung

Naunyn-Schmiedeberg s Archives of Pharmacology ◽

10.1007/bf00170846 ◽

1996 ◽

Vol 354 (5) ◽

Cited By ~ 4

Author(s):

Stefan Uhlig ◽

RolandLewis Featherstone ◽

Albrect Wendel ◽

Otto-Henning Wilhelms

Keyword(s):

Platelet Activating Factor ◽

Rat Lung ◽

Edema Formation ◽

Isolated Rat Lung ◽

Isolated Rat

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High airway-to-blood transport of an opioid tetrapeptide in the isolated rat lung after aerosol delivery

Peptides ◽

10.1016/s0196-9781(01)00624-6 ◽

2002 ◽

Vol 23 (3) ◽

pp. 469-478 ◽

Cited By ~ 14

Author(s):

Ann Tronde ◽

Eva Krondahl ◽

Hans von Euler-Chelpin ◽

Per Brunmark ◽

Ursula Hultkvist Bengtsson ◽

...

Keyword(s):

Rat Lung ◽

Aerosol Delivery ◽

Blood Transport ◽

Isolated Rat Lung ◽

Isolated Rat

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Hypoxia recruits intrapulmonary arteriovenous pathways in intact rats but not isolated rat lungs

Journal of Applied Physiology ◽

10.1152/japplphysiol.00985.2011 ◽

2012 ◽

Vol 112 (11) ◽

pp. 1915-1920 ◽

Cited By ~ 18

Author(s):

Melissa L. Bates ◽

Brendan R. Fulmer ◽

Emily T. Farrell ◽

Alyssa Drezdon ◽

David F. Pegelow ◽

...

Keyword(s):

Intact Animal ◽

Large Diameter ◽

Rat Lung ◽

Isolated Lung ◽

Alveolar Hypoxia ◽

Spontaneously Breathing ◽

Isolated Rat Lung ◽

Mixed Venous ◽

Isolated Rat ◽

Intact Rats

Intrapulmonary arteriovenous anastomoses (IPAVS) directly connect the arterial and venous circulations in the lung, bypassing the capillary network. Here, we used solid, latex microspheres and isolated rat lung and intact, spontaneously breathing rat models to test the hypothesis that IPAVS are recruited by alveolar hypoxia. We found that hypoxia recruits IPAVS in the intact rat, but not the isolated lung. IPAVS are at least 70 μm in the rat and, interestingly, appear to be recruited when the mixed venous Po2 falls below 22 mmHg. These data provide evidence that large-diameter, direct arteriovenous connections exist in the lung and are recruitable by hypoxia in the intact animal.

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Control of release of surfactant phospholipids in the isolated perfused rat lung

Journal of Applied Physiology ◽

10.1152/jappl.1981.51.1.90 ◽

1981 ◽

Vol 51 (1) ◽

pp. 90-98 ◽

Cited By ~ 72

Author(s):

T. E. Nicholas ◽

H. A. Barr

Keyword(s):

Tidal Volume ◽

Type Ii ◽

Rat Lung ◽

Cyclic Monophosphate ◽

Type Ii Cell ◽

Surfactant Phospholipids ◽

Isolated Rat Lung ◽

Isolated Rat

We used the isolated rat lung to investigate surfactant release. The lung was ventilated at 60.min-1 with 5% CO2–95% O2 and perfused at 10 ml.min-1 with Krebs-bicarbonate (4.5% albumin). After 20 min during which antagonist drugs were present, the lungs were either hyperventilated or agonist drugs were added. After another 15 min lungs were lavaged. Peak inspired pressures (PIP) in excess of 12 cmH2O produced progressively greater phospholipid (PL) yields. Whereas ventilating with PIP of 9 cmH2O and end-expired pressure(EEP) of 5 cmH2O produced 5.9 +/- 0.8 (mean +/-SD) (n = 17) mg PL. g dry lung-1, ventilating with PIP of 20 cmH2O and EEP of 0 cmH2O produced 10.1 +/- 1.3 (n = 26). PL release was unaffected by tetrodotoxin, propranolol, atropine, cyproheptadine, or indomethacin. PL was increased by salbutamol and dibutyryl adenosine 3',5'-cyclic monophosphate but not by pilocarpine or dibutyryl guanosine 3',5'-cyclic monophosphate. We conclude, that increasing tidal volume immediately releases surfactant, probably by distorting the type II cell and elevating cAMP. An intrapulmonary neural reflex is not involved in this response of the isolated rat lung, nor is histamine, 5-hydroxytryptamine, or a prostaglandin.

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Pulmonary circulation demonstration using an isolated rat lung model.

AJP Advances in Physiology Education ◽

10.1152/advances.1998.275.6.s85 ◽

1998 ◽

Vol 275 (6) ◽

pp. S85

Author(s):

T C Resta ◽

L M Eichinger ◽

R D Russ ◽

B R Walker

Keyword(s):

Pulmonary Circulation ◽

Lung Model ◽

Physiological Data ◽

Teaching Tool ◽

Rat Lung ◽

Laboratory Exercise ◽

Vascular Physiology ◽

Basic Concepts ◽

Isolated Rat Lung ◽

Experimental Preparation

We have developed a pulmonary circulation laboratory exercise that effectively illustrates basic concepts typically taught in a graduate physiology curriculum. The demonstration uses an isolated, perfused rat lung model to delineate the mechanisms by which pulmonary vascular resistance can be altered either passively or in an active manner by contraction or relaxation of vascular smooth muscle. The exercise further offers an opportunity to closely observe an experimental preparation commonly used to study the pulmonary circulation and allows students the opportunity to interpret the resulting physiological data. Student evaluations indicate that the demonstration was received with enthusiasm and provides an effective teaching tool for reinforcing concepts in pulmonary vascular physiology.

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Factors controlling the metabolic response to glucose in isolated rat lung cells

Life Sciences ◽

10.1016/0024-3205(77)90454-4 ◽

1977 ◽

Vol 20 (9) ◽

pp. 1599-1605 ◽

Cited By ~ 2

Author(s):

Julio Pérez-Díaz ◽

Angeles Martín Requero ◽

Matilde S. Ayuso-Parrilla ◽

Roberto Parrilla

Keyword(s):

Metabolic Response ◽

Lung Cells ◽

Rat Lung ◽

Isolated Rat Lung ◽

Isolated Rat

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Measurements on the Elasticity of the Isolated Rat Lung

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1951.167.3.840-t ◽

1951 ◽

Vol 167 (3) ◽

pp. 840-840 ◽

Cited By ~ 1

Author(s):

Richard W. Lawton ◽

Doyle Joslin

Keyword(s):

Lung Volume ◽

Rat Lung ◽

Total Lung Volume ◽

Page Figure ◽

Isolated Rat Lung ◽

Isolated Rat

Page 117. Richard W. Lawton and Doyle Joslin, "Measurements on the Elasticity of the Isolated Rat Lung." Lines 11 to 7 from bottom of page, figure 7, and reference (12). Add the following statement: "At the end of a normal expiration the total lung volume is of the order of 5 cc. (12) or equivalent to the calculated V0 in this case. Tidal air should lie, therefore, between 0 and 1.0 to 1.5 cc. on the ordinate."

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