Influence of hypoxia and serotonin on small pulmonary vessels

1994 ◽  
Vol 76 (1) ◽  
pp. 56-64 ◽  
Author(s):  
A. al-Tinawi ◽  
G. S. Krenz ◽  
D. A. Rickaby ◽  
J. H. Linehan ◽  
C. A. Dawson
Keyword(s):  
Size Range ◽  
Pulmonary Arteries ◽  
The Other ◽  
Internal Diameter ◽  
Total Response ◽  
Pulmonary Vessels ◽  
X Ray ◽  
Diameter Range ◽  
Maximum Decrease ◽  
Potential Impact

X-ray angiograms obtained from isolated perfused dog lungs were used to measure changes in the internal diameter of small intraparenchymal pulmonary arteries (150–1,600 microns) and veins (200–1,000 microns) in response to hypoxia or intra-arterial serotonin [5-hydroxytryptamine (5-HT)] infusion. The diameter changes in response to the two stimuli were measured over a range of stimulus-induced increases (delta Pa) in the total arteriovenous pressure drop. When the resulting delta Pa was small, all arteries in the diameter range studied constricted in response to either stimuli. The maximum decrease in diameter was approximately 25% with hypoxia and 36% with 5-HT. However, when delta Pa was large, arteries with a control diameter larger than approximately 800 microns distended with hypoxia. On the other hand, 5-HT constricted all the arteries in the size range studied regardless of the resulting magnitude of delta Pa. Hypoxia caused a small (approximately 9%) constriction in all veins in the diameter range studied independent of diameter or the magnitude of delta Pa, whereas in the concentration range studied 5-HT had no significant influence on these veins. An analysis of the potential impact of these vessels on total pulmonary vascular resistance suggested that although vessels in the size range studied contributed significantly to the total response to these two stimuli, vessels smaller than those studied also made a major contribution to the total response.

Effects of regional alveolar hypoxia and hypercapnia on small pulmonary vessels in cats

1986 ◽  
Vol 61 (2) ◽  
pp. 440-448 ◽  
Author(s):  
M. Shirai ◽  
K. Sada ◽  
I. Ninomiya
Keyword(s):  
Flow Velocity ◽  
Volume Flow ◽  
The Other ◽  
Internal Diameter ◽  
Lung Region ◽  
Pulmonary Vessels ◽  
Small Arteries ◽  
X Ray ◽  
Other Hand ◽  
Alveolar Hypoxia

Using an X-ray TV system, we analyzed responses in the internal diameter (ID), flow velocity, and volume flow in small pulmonary vessels (100–600 microns ID) during unilobar hypoxia and hypercapnia in cats. In the hypoxic and hypercapnic lobes, the ID reduced in proportion to the degree of hypoxia and hypercapnia, respectively. The ID reduction was larger in the arteries than in the veins for a given stimulus. In the arteries, the ID reduced nonuniformly in the series-arranged vessels in response to both stimuli. The percentage ID reduction was maximal in the arteries of 200–300 microns ID, in which it was 21, 26, 28, and 36% with 5% O2, 0% O2, 5% CO2, and 10% CO2 inhalations, respectively. On the other hand, in the veins, uniform ID reduction occurred for a given stimulus. In the contralateral normoxic lobe, the ID did not change significantly. In both hypoxic and hypercapnic lobes, the flow velocity and volume flow of the small arteries decreased, with 5% O2, by 18 and 40%, respectively, and, with 5% CO2, by 23 and 50%, respectively. In contrast, in the normoxic lobe, they increased significantly during 5% O2 and 5% CO2 inhalations. We concluded that regional alveolar hypoxia and hypercapnia induced a local vasoconstriction particularly in the small arteries of 200–300 microns ID and decreased the flow velocity and volume flow in the same lung region.

Vagally and acetylcholine-mediated constriction in small pulmonary vessels of rabbits

1987 ◽  
Vol 63 (4) ◽  
pp. 1601-1609 ◽  
Author(s):  
K. Sada ◽  
M. Shirai ◽  
I. Ninomiya
Keyword(s):  
Nerve Stimulation ◽  
Pulmonary Arteries ◽  
Stimulus Frequency ◽  
Vagal Nerve ◽  
Internal Diameter ◽  
Specific Stimulus ◽  
Pulmonary Vessels ◽  
X Ray ◽  
Branching Points ◽  
Arteries And Veins

Using a new X-ray TV system, we analyzed effects of vagal nerve stimulation (VNS; 1–30 Hz) and intravenous injection of acetylcholine (Ach; 0.3–0.9 microgram) on the internal diameter (ID; 100–1,500 microns) of small pulmonary arteries and veins in anesthetized rabbits. In selective segments of the arteries, ID decreased abruptly and maximally by 50–70% in a specific stimulus frequency to the vagal nerve and a dose of ACh. The vasoconstrictor sites were distributed near the branching points of the arteries, particularly those downstream, and their numbers increased with an increase in the stimulus frequencies and ACh doses. The relative frequencies of occurrences were 15.3% with VNS (30 Hz) and 5.3% with ACh (0.9 microgram). In nonselective segments with VNS, ID decreased frequency dependently by 0, 4, 12, and 26% at 1, 4, 15, and 30 Hz, respectively, and with ACh, decreased dose dependently by 21 and 35% with 0.3 and 0.9 microgram, respectively. The vasoconstriction in response to VNS and ACh was attenuated by atropine, enhanced by eserine, and not affected by phentolamine. That vasoconstriction to VNS was abolished by hexamethonium. No selective constriction was found in veins and the ID was decreased uniformly by 1–2% with VNS and ACh.

Potent vasodilator responses to human urotensin-II in human pulmonary and abdominal resistance arteries

2001 ◽  
Vol 280 (2) ◽  
pp. H925-H928 ◽  
Author(s):  
Alison Stirrat ◽  
Marie Gallagher ◽  
Stephen A. Douglas ◽  
Eliot H. Ohlstein ◽  
Colin Berry ◽  
...  
Keyword(s):  
Sodium Nitroprusside ◽  
Vascular Function ◽  
Pulmonary Arteries ◽  
Systemic Resistance ◽  
Internal Diameter ◽  
Urotensin Ii ◽  
Resistance Arteries ◽  
Pulmonary Vessels ◽  
Potent Vasodilator ◽  
Abdominal Arteries

The peptide human urotensin-II (hUT-II) and its receptor have recently been cloned. The vascular function of this peptide in humans, however, has yet to be determined. Vasoconstrictor and vasodilator responses to hUT-II were investigated in human small muscular pulmonary arteries [∼170 μm internal diameter (ID)] and human abdominal resistance arteries (∼200 μm ID). Vasodilator responses were investigated in endothelin-1 (3 nM) precontracted vessels and, in the small pulmonary vessels, compared with the known vasodilators adrenomedullin, sodium nitroprusside, and acetylcholine. In human small pulmonary arteries, hUT-II did not induce vasoconstriction but was a potent vasodilator [−log M concentration causing 50% of the maximum vasodilator effect (pIC50) 10.4 ± 0.5; percentage of reduction in tone ( E max) 81 ± 8% (vs. 23 ± 11% in time controls), n = 5]. The order of potency for vasodilation was human urotensin-II = adrenomedullin (pIC50 10.1 ± 0.4, n = 6) > sodium nitroprusside (pIC50 7.4 ± 0.2, n = 6) = acetylcholine (pIC50 6.8 ± 0.3, n = 6). In human abdominal arteries, hUT-II did not induce vasoconstriction but was a potent vasodilator [pIC50 10.3 ± 0.7; E max96 ± 8% (vs. 43 ± 16% in time controls), n = 4]. This is the first report that hUT-II is a potent vasodilator but not a vasoconstrictor of human small pulmonary arteries and systemic resistance arteries.

scholarly journals On the influence of the respiratory organs in regulating the quantity of blood within the heart

1837 ◽  
Vol 3 ◽  
pp. 342-343
Keyword(s):  
Pulmonary Arteries ◽  
The Other ◽  
Pulmonary Vessels ◽  
Arterial Circulation ◽  
Arterial Blood ◽  
Other Hand ◽  
Venae Cavae

The author observes that the act of inspiration tends not only to favour the passage of the blood into the venæ cavæ, but also to detain it in the pulmonary vessels,—in consequence of the expansion of the lungs allowing of its more ready ingress into the pulmonary arteries, and impeding its exit by the veins—and thus retards its return to the heart. On the other hand, the collapse both of the lungs and of the parietes of the chest, during expiration, assists the transmission of arterial blood from the lungs into the left cavities of the heart, and promotes its passage into the aorta. Thus he considers inspiration as an auxiliary to the venous, and expiration to the arterial, circulation; the first acting like a sucking, and the latter like a forcing pump, in aiding the power of the heart. On this principle he explains the influence exerted on the circulation and on the action of the heart by various modes of respiration, whether voluntary or involuntary, in different circumstances. Laughter, crying, weeping, sobbing and sighing, &c., he considers as efforts made with a view to effect certain alterations in the quantity of blood in the lungs and heart, when the circulation has been disturbed by mental emotions.

X-ray TV system for measuring microcirculation in small pulmonary vessels

1985 ◽  
Vol 59 (3) ◽  
pp. 1013-1018 ◽  
Author(s):  
K. Sada ◽  
M. Shirai ◽  
I. Ninomiya
Keyword(s):  
Flow Velocity ◽  
Volume Flow ◽  
Internal Diameter ◽  
Local Circulation ◽  
Cross Sectional ◽  
Pulmonary Vessels ◽  
X Ray ◽  
Transit Times ◽  
Time Required ◽  
Processing Device

We developed a new system that consists of 1) a specially designed X-ray apparatus, 2) an X-ray-sensitive 1-in. Vidicon camera, and 3) a digital image-processing device. The picture element is approximately 20 micron in size, and the time required for one frame is 1/30 s. Using this system, we measured the internal diameter (ID), the cross-sectional area, flow velocity, volume flow, and transit time of small pulmonary vessels of approximately 100–500 micron at control and with serotonin in anesthetized cats. Flow velocity and volume flow from large [458 +/- 22 (SE) micron] to small (340 +/- 32 micron) arteries were 5.4 +/- 0.4 cm/s and 0.53 +/- 0.06 ml/min, respectively. Transit times of the contrast medium from large to small arteries (Ta) and to large veins (Tv) were 0.68 +/- 0.04 and 3.71 +/- 0.25 s, respectively. Serotonin injection (20–30 micrograms/kg iv) decreased ID, flow velocity, and volume flow of arteries by 8–48, 32, and 76%, respectively, whereas Ta and Tv increased by 91 and 69%, respectively. The system can provide useful information regarding the local circulation in the lung.

Effect of Ammonia on the SiO2 Colloidal Particles Synthesized by the Stöber Method

2017 ◽  
Vol 865 ◽  
pp. 25-29 ◽  
Author(s):  
Yun Gao Cai ◽  
Xin Qi Li
Keyword(s):  
Size Distribution ◽  
Room Temperature ◽  
Colloidal Particles ◽  
Size Range ◽  
Tetraethyl Orthosilicate ◽  
The Other ◽  
X Ray Diffraction ◽  
X Ray ◽  
Result Show ◽  
Scanning Electron

Various sizes SiO2 colloidal particles in the size range of 260-950 nm were synthesized by the stöber method by adjusting the amount of ammonia from 9.0 ml to 3.0 ml while keeping 20.0 ml tetraethyl orthosilicate (TEOS), 125.0 ml ethanol, 6.0 ml ammonia and 18.0 ml distilled water fixed. In addition, X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed to analyze the crystallinity and morphology of the synthesized SiO2 colloidal particles; the XRD result show that the SiO2 colloidal particles are amorphous at room temperature; the SEM results demonstrated that the amount of ammonia could have significant effects on the size, size distribution and sphericity of the SiO2 colloidal particles. SiO2 colloidal particles were resulted with good monodispersity when the amount of ammonia was in the range of 6.0-90 ml, while SiO2 colloidal particles with double size distribution were obtained when the range is 3.0-4.5 ml; on the other hand, SiO2 spheres were resulted with good sphericity when the ammonia is in the range of 6.0-7.5 ml.

Inhaled nitric oxide: diameter response patterns in feline small pulmonary arteries and veins

1996 ◽  
Vol 270 (3) ◽  
pp. H974-H980 ◽  
Author(s):  
M. Shirai ◽  
A. Shimouchi ◽  
A. T. Kawaguchi ◽  
K. Sunagawa ◽  
I. Ninomiya
Keyword(s):  
Nitric Oxide ◽  
Pulmonary Arteries ◽  
Internal Diameter ◽  
Response Patterns ◽  
Television System ◽  
X Ray ◽  
Small Vessels ◽  
Pulmonary Vasoconstriction ◽  
Arteries And Veins

Using an X-ray television system on the in vivo cat lung, we directly measured internal diameter (ID) changes in the small pulmonary arteries and veins (100-1,100 microns ID) in response to 5, 15, and 40 ppm nitric oxide (NO) inhalations. We also measured to what extent 40 ppm NO inhalation can attenuate large ID constrictions at the different serial segments of the small vessels due to unilobar anoxic (0% O2) exposure. Under normoxic conditions, 5-40 ppm NO inhalations significantly increased the ID of both arteries and veins less than approximately 900 microns dose dependently but caused no significant, or only slight, ID increases in the vessels larger than this, if any at all. The ID increase in the serially connected arteries was nonuniform (4-18, 8-28, and 7-35% with 5, 15, and 40 ppm NO inhalations, respectively), whereas that for the veins was relatively uniform (4-9, 6-17, and 7-18% with 5, 15, and 40 ppm NO, respectively). The maximum ID increase occurred in the 200- to 500- and 200- to 700-microns arteries in response to 5-15 and 40 ppm NO, respectively. Unilobar anoxic exposure significantly decreased the ID of the 100- to 700-microns arteries and veins, but not the ID of the other-sized vessels. The ID decrease in the serially connected arteries was nonuniform (13-29%) but relatively uniform in the veins (8-12%). The maximum ID decrease occurred in the 200- to 300-microns arteries. However, adding 40 ppm NO to the lobe completely eradicated the ID decreases at all segments of the arteries and veins and, instead, caused significant ID increase (11-21%) in the arteries and (10-12%) in the veins. The data indicate that, according to dosage, 5-40 ppm NO inhalations cause selective dilation of approximately 100- to 900-microns pulmonary arteries and veins, particularly the 200- to 700-microns arteries. During anoxic exposure, the vasodilator effect of NO is preserved and can completely reverse the marked pulmonary vasoconstriction.

Comparison of Silica Sand Properties from Kandal Province, Cambodia and Tapah, Perak, Malaysia and Characterization of Soda Lime Silicate Glass Produced From Cambodian Silica Sand

2013 ◽  
Vol 858 ◽  
pp. 248-253 ◽  
Author(s):  
Em Sereiratana ◽  
Khairul Anwar Bharum ◽  
S.A. Rezan ◽  
Radzali Othman ◽  
Fumitake Takahashi ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Melting Temperature ◽  
Size Range ◽  
Soda Lime ◽  
The Other ◽  
Silica Sand ◽  
Particle Size Range ◽  
Soaking Time ◽  
X Ray

Silica sand from Kandal province, Cambodia and Tapah Perak, Malaysia was grounded into an average micron size of 128.12 and 132.68µm. Both sands were characterized by X-ray fluorescence (XRF), X-ray Diffraction, particle Size Analysis, Differential Thermal Analysis and Thermogravimetric Analysis (DTA/TGA). Malaysian silica sand was designated SDMTP and Cambodian Silica sand as SDCK. From theanalysis, XRF showed that the major impurities in SDMTP were Al2O3, K2O and TiO2. On the other hand, SDCK had impurities of Al2O3,K2O and Na2O. DTA results from SDMTP and SDCK showedthere is an endothermic peak occurring at 572°C which can be attributed to β-quartz transformation into α-quartz. TGA for SDMTP showed that maximum weight lost was at 441°C with a weight percent (wt%) change of 0.48%. The TGA for SDCK showed a wt% change of 1.298% at temperature of 1000°C. From XRD analysis, the main phase of SDCK and SDMTP were quartz. The impurities of both sands play an important role in determining the optical and mechanical properties of the soda lime silicate (SLS) glass formed. Particle size of silica sand affects the mechanical properties such as compression, hardness, and transmittance of SLS glass. The smaller particle size would be ideal choice for glassmaking. Melting temperature, soaking time, and melt accelerant can also affect the mechanical properties of SLS glass. The best result obtained for Vickers hardness in this study was the SLS glass sample designated as Run No 12 with a value of 525.02 kg.mm-2. It had a particle size range from 500-600µm, a furnace soaking time of 4 hours at a melting temperature of 1500°C with 1.0 wt% of Sodium Chloride (NaCl) as meltingaccelerant. On the other hand, the highest compressive strength of 356.22 MPa was found in sample designated as Run No 1. It had a particle size range from 75-1800µm, a soaking time of 5 hours at a melting temperature of 1550°C with 0.5 wt% of NaCl. Lastly,the highest UV-VIS transmittance at 520 nm was obtained from sample designated as Run No 5 within the value of 84.26 %Transmittance (T). It had a particle size range of 75-1800µm, soaking time of 3 hours at a melting temperature of 1550°C with 1.5 wt% of NaCl. .

Microchemical imaging in biomedical research

1992 ◽  
Vol 50 (2) ◽  
pp. 1118-1119
Author(s):  
P. Ingram
Keyword(s):  
Data Analysis ◽  
Electron Probe ◽  
The Other ◽  
X Ray ◽  
Cell Element ◽  
Physiological Information ◽  
Functional States ◽  
Elemental Maps ◽  
Electron Energy Loss ◽  
Secondary Ion

It is well established that unique physiological information can be obtained by rapidly freezing cells in various functional states and analyzing the cell element content and distribution by electron probe x-ray microanalysis. (The other techniques of microanalysis that are amenable to imaging, such as electron energy loss spectroscopy, secondary ion mass spectroscopy, particle induced x-ray emission etc., are not addressed in this tutorial.) However, the usual processes of data acquisition are labor intensive and lengthy, requiring that x-ray counts be collected from individually selected regions of each cell in question and that data analysis be performed subsequent to data collection. A judicious combination of quantitative elemental maps and static raster probes adds not only an additional overall perception of what is occurring during a particular biological manipulation or event, but substantially increases data productivity. Recent advances in microcomputer instrumentation and software have made readily feasible the acquisition and processing of digital quantitative x-ray maps of one to several cells.

A STUDY ON THE CORRELATION BETWEEN MORPHOLOGIC ANORMALIES AND LEFT VENTRICULAR DIASTOLIC FUNCTION IN DILATED CARDIO-MYOPATHY

2011 ◽  
pp. 137-144
Author(s):  
Thi Ngoc Ha Hoang ◽  
Anh Vu Nguyen ◽  
Minh Loi Hoang ◽  
Cuu Long Nguyen ◽  
Thi Thuy Hang Nguyen
Keyword(s):  
Pulmonary Artery ◽  
Dilated Cardiomyopathy ◽  
Diastolic Dysfunction ◽  
Diastolic Function ◽  
Pulmonary Arteries ◽  
Left Ventricular ◽  
University Hospital ◽  
Cross Sectional ◽  
X Ray ◽  
Key Words Dilated Cardiomyopathy

Purposes: Describe the morphological and diastolic function of left ventricular changes in the patients with dilated cardiomyopathy (DCM) on US, X-ray findings, and Evaluate the correlation between morphology and diastolic function of left ventricular. Materials and method: Cross sectional study from Dec 2009 to Aug 2010, on 39 patients with dilated cardiomyopathy were evaluated at the University Hospital of Hue College of Medical and Pharmaceutical. Results: 1. X-ray and US findings characteristics of DCM is significantly increased in diameter of L, H and mG; LVM, LVMI, LVDd and LAD. 2. The pression of pulmonary artery has been significantly increased with redistribution pulmonary arteries in 61.5% cases and 23.1% have reversed pulmonary artery distribution. 3. DCM have diastolic dysfunction in 100% patients, including severe disorders to 61.5%; the restrictive dysfunction has ratio E/A>2 and E/Em average was 23.89± 17.23. 4.The correlation between the morphology and function in DCM: the diameter of H and L on the X-ray, LAD and ratio LA/AO on US correlated with the level of diastolic dysfunction (p< 0.05). All three radiographic parameters on the radio standard (H, L, the index Cardio/Thoracic) and LVDd on US have negative correlated with EF and FS with p <0.05. Key words: dilated cardiomyopathy, diastolic dysfunction, cardiac tissue Doppler, reversed pulmonary artery distribution

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