Microlymphatic and tissue oxygen tension in the rat mesentery

2004 ◽  
Vol 286 (3) ◽  
pp. H878-H883 ◽  
Author(s):  
Nanae Hangai-Hoger ◽  
Pedro Cabrales ◽  
Juan C. Briceño ◽  
Amy G. Tsai ◽  
Marcos Intaglietta
Keyword(s):  
Adipose Tissue ◽  
Vessel Wall ◽  
Lymphatic Vessels ◽  
Surrounding Tissue ◽  
Tissue Oxygen ◽  
Phosphorescence Quenching ◽  
Rat Mesentery ◽  
Lymph Fluid ◽  
The Difference ◽  
Lymphatic Fluid

Oxygen phosphorescence quenching was used to measure tissue Po2 of lymphatic vessels of 43.6 ± 23.1 μm (mean ± SD) diameter in tissue locations of the rat mesentery classified according to anatomic location. Lymph and adipose tissue Po2 were 20.6 ± 9.1 and 34.1 ± 7.8 mmHg, respectively, with the difference being statistically significant. Rare microlymphatic vessels in connective tissue not surrounded by microvessels had a Po2 of 0.8 ± 0.2 mmHg, whereas the surrounding tissue Po2 was 3.0 ± 3.2 mmHg, with both values being significantly lower than those of adipose tissue. Lower of lymph fluid Po2 relative to the surrounding tissue was also evident in paired measurements of Po2 in the lymphatic vessels and perilymphatic adipose tissue, which was significantly lower than the Po2 in paired adipose tissue. The Po2 of the lymphatic fluid of the mesenteric microlymphatics is consistently lower than that of the surrounding adipose tissue by ∼11 mmHg; therefore, lymph fluid has the lowest Po2 of this tissue. The disparity between lymph and tissue Po2 is attributed to the microlymphatic vessel wall and lymphocyte oxygen consumption.

Intravascular oxygen distribution in subcutaneous 9L tumors and radiation sensitivity

1997 ◽  
Vol 82 (6) ◽  
pp. 1939-1945 ◽  
Author(s):  
George J. Cerniglia ◽  
David F. Wilson ◽  
Marek Pawlowski ◽  
Sergei Vinogradov ◽  
John Biaglow
Keyword(s):  
Tumor Vasculature ◽  
Radiation Sensitivity ◽  
Surrounding Tissue ◽  
Oxygen Distribution ◽  
Tissue Oxygen ◽  
Phosphorescence Quenching ◽  
Tumor Identification ◽  
Oxygen Measurements

Cerniglia, George J., David F. Wilson, Marek Pawlowski, Sergei Vinogradov, and John Biaglow. Intravascular oxygen distribution in subcutaneous 9L tumors and radiation sensitivity. J. Appl. Physiol. 82(6): 1939–1945, 1997.—Phosphorescence quenching was evaluated as a technique for measuring [Formula: see text] in tumors and for determining the effect of increased[Formula: see text] on sensitivity of the tumors to radiation. Suspensions of cultured 9L cells or small pieces of solid tumors from 9L cells were injected subcutaneously on the hindquarter of rats, and tumors were grown to between 0.2 and 1.0 cm in diameter. Oxygen-dependent quenching of the phosphorescence of intravenously injected Pd-meso-tetra-(4-carboxyphenyl) porphine was used to image the in vivo distribution of [Formula: see text] in the vasculature of small tumors and surrounding tissue. Maps (512 × 480 pixels) of tissue oxygen distribution showed that the[Formula: see text] within 9L tumors was low (2–12 Torr) relative to the surrounding muscle tissue (20–40 Torr). When the rats were given 100% oxygen or carbogen (95% O2-5% CO2) to breathe, the[Formula: see text] in the tumors increased significantly. This increase was variable among tumors and was greater with carbogen compared with 100% oxygen. Based on irradiation and regrowth studies, carbogen breathing increased the sensitivity of the tumors to radiation. This is consistent with the measured increase in[Formula: see text] in the tumor vasculature. It is concluded that phosphorescence quenching can be used for noninvasive determination of the oxygenation of tumors. This method for oxygen measurements has great potential for clinical application in tumor identification and therapy.

scholarly journals The rate of O2 loss from mesenteric arterioles is not unusually high

2011 ◽  
Vol 301 (3) ◽  
pp. H737-H745 ◽  
Author(s):  
Aleksander S. Golub ◽  
Bjorn K. Song ◽  
Roland N. Pittman
Keyword(s):  
Respiration Rate ◽  
Volume Fraction ◽  
Vascular Wall ◽  
Surrounding Tissue ◽  
Disappearance Rate ◽  
Estimation Of Parameters ◽  
Phosphorescence Quenching ◽  
Rat Mesentery ◽  
Exponential Decline ◽  
Arteriolar Wall

The O2 disappearance curve (ODC) recorded in an arteriole after the rapid arrest of blood flow reflects the complex interaction among the dissociation of O2 from hemoglobin, O2 diffusivity, and rate of respiration in the vascular wall and surrounding tissue. In this study, the analysis of experimental ODCs allowed the estimation of parameters of O2 transport and O2 consumption in the microcirculation of the mesentery. We collected ODCs from rapidly arrested blood inside rat mesenteric arterioles using scanning phosphorescence quenching microscopy (PQM). The technique was used to prevent the artifact of accumulated O2 photoconsumption in stationary media. The observed ODC signatures were close to linear, in contrast to the reported exponential decline of intra-arteriolar Po2. The rate of Po2 decrease was 0.43 mmHg/s in 20-μm-diameter arterioles. The duration of the ODC was 290 s, much longer than the 12.8 s reported by other investigators. The arterioles associated with lymphatic microvessels had a higher O2 disappearance rate of 0.73 mmHg/s. The O2 flux from arterioles, calculated from the average O2 disappearance rate, was 0.21 nl O2·cm−2·s−1, two orders of magnitude lower than reported in the literature. The physical upper limit of the O2 consumption rate by the arteriolar wall, calculated from the condition that all O2 is consumed by the wall, was 452 nl O2·cm−3·s−1. From consideration of the microvascular tissue volume fraction in the rat mesentery of 6%, the estimated respiration rate of the vessel wall was ∼30 nl O2·cm−3·s−1. This result was three orders of magnitude lower than the respiration rate in rat mesenteric arterioles reported by other investigators. Our results demonstrate that O2 loss from mesenteric arterioles is small and that the O2 consumption by the arteriolar wall is not unusually large.

scholarly journals Changes in Children’s Body Composition and Posture during Puberty Growth

Children ◽  
2021 ◽  
Vol 8 (4) ◽  
pp. 288
Author(s):  
Wojciech Rusek ◽  
Joanna Baran ◽  
Justyna Leszczak ◽  
Marzena Adamczyk ◽  
Rafał Baran ◽  
...  
Keyword(s):  
Body Composition ◽  
Adipose Tissue ◽  
Regression Analysis ◽  
Body Mass ◽  
Pelvic Obliquity ◽  
The Body ◽  
Body Posture ◽  
Older Children ◽  
The Difference ◽  
The Right

The main goal of our study was to determine how the age of children, puberty and anthropometric parameters affect the formation of body composition and faulty body posture development in children. The secondary goal was to determine in which body segments abnormalities most often occur and how gender differentiates the occurrence of adverse changes in children’s body posture and body composition during puberty. The study group consisted of 464 schoolchildren aged from 6–16. Body posture was assessed with the Zebris system. The composition of the body mass was tested with Tanita MC 780 MA body mass analyzer and the body height was measured using a portable stadiometer PORTSTAND 210. The participants were further divided due to the age of puberty. Tanner division was adopted. The cut-off age for girls is ≥10 years and for boys it is ≥12 years. The analyses applied descriptive statistics, the Pearson correlation, stepwise regression analysis and the t-test. The accepted level of significance was p < 0.05. The pelvic obliquity was lower in older children (beta = −0.15). We also see that age played a significant role in the difference in the height of the right pelvis (beta = −0.28), and the difference in the height of the right shoulder (beta = 0.23). Regression analysis showed that the content of adipose tissue (FAT%) increased with body mass index (BMI) and decreased with increasing weight, age, and height. Moreover, the FAT% was lower in boys than in girls (beta negative equal to −0.39). It turned out that older children (puberty), had greater asymmetry in the right shoulder blade (p < 0.001) and right shoulder (p = 0.003). On the other hand, younger children (who were still before puberty) had greater anomalies in the left trunk inclination (p = 0.048) as well as in the pelvic obliquity (p = 0.008). Girls in puberty were characterized by greater asymmetry on the right side, including the shoulders (p = 0.001), the scapula (p = 0.001) and the pelvis (p < 0.001). In boys, the problem related only to the asymmetry of the shoulder blades (p < 0.001). Girls were characterized by a greater increase in adipose tissue and boys by muscle tissue. Significant differences also appeared in the body posture of the examined children. Greater asymmetry within scapulas and shoulders were seen in children during puberty. Therefore, a growing child should be closely monitored to protect them from the adverse consequences of poor posture or excessive accumulation of adipose tissue in the body.

scholarly journals Determinants of valve gating in collecting lymphatic vessels from rat mesentery

2011 ◽  
Vol 301 (1) ◽  
pp. H48-H60 ◽  
Author(s):  
Michael J. Davis ◽  
Elaheh Rahbar ◽  
Anatoliy A. Gashev ◽  
David C. Zawieja ◽  
James E. Moore
Keyword(s):  
Pressure Gradient ◽  
Muscle Tone ◽  
Lymphatic Vessels ◽  
Vessel Diameter ◽  
Intraluminal Pressure ◽  
Pressure Gradients ◽  
Rat Mesentery ◽  
Temporal Relationships ◽  
Wide Range ◽  
Valve Opening

Secondary lymphatic valves are essential for minimizing backflow of lymph and are presumed to gate passively according to the instantaneous trans-valve pressure gradient. We hypothesized that valve gating is also modulated by vessel distention, which could alter leaflet stiffness and coaptation. To test this hypothesis, we devised protocols to measure the small pressure gradients required to open or close lymphatic valves and determine if the gradients varied as a function of vessel diameter. Lymphatic vessels were isolated from rat mesentery, cannulated, and pressurized using a servo-control system. Detection of valve leaflet position simultaneously with diameter and intraluminal pressure changes in two-valve segments revealed the detailed temporal relationships between these parameters during the lymphatic contraction cycle. The timing of valve movements was similar to that of cardiac valves, but only when lymphatic vessel afterload was elevated. The pressure gradients required to open or close a valve were determined in one-valve segments during slow, ramp-wise pressure elevation, either from the input or output side of the valve. Tests were conducted over a wide range of baseline pressures (and thus diameters) in passive vessels as well as in vessels with two levels of imposed tone. Surprisingly, the pressure gradient required for valve closure varied >20-fold (0.1–2.2 cmH2O) as a passive vessel progressively distended. Similarly, the pressure gradient required for valve opening varied sixfold with vessel distention. Finally, our functional evidence supports the concept that lymphatic muscle tone exerts an indirect effect on valve gating.

Estimating oxygen consumption rates of arteriolar walls under physiological conditions in rat skeletal muscle

2005 ◽  
Vol 289 (1) ◽  
pp. H295-H300 ◽  
Author(s):  
Masahiro Shibata ◽  
Shigeru Ichioka ◽  
Akira Kamiya
Keyword(s):  
Vascular Tone ◽  
Consumption Rate ◽  
Vascular Wall ◽  
Surrounding Tissue ◽  
Phosphorescence Quenching ◽  
Physiological Conditions ◽  
First Order ◽  
Vascular Walls ◽  
Consumption Rates

To examine the effects of vascular tone reduction on O2 consumption of the vascular wall, we determined the O2 consumption rates of arteriolar walls under normal conditions and during vasodilation induced by topical application of papaverine. A phosphorescence quenching technique was used to quantify intra- and perivascular Po2 in rat cremaster arterioles with different branching orders. Then, the measured radial Po2 gradients and a theoretical model were used to estimate the O2 consumption rates of the arteriolar walls. The vascular O2 consumption rates of functional arterioles were >100 times greater than those observed in in vitro experiments. The vascular O2 consumption rate was highest in first-order (1A) arterioles, which are located upstream, and sequentially decreased downstream in 2A and 3A arterioles under normal conditions. During papaverine-induced vasodilation, on the other hand, the O2 consumption rates of the vascular walls decreased to similar levels, suggesting that the high O2 consumption rates of 1A arterioles under normal conditions depend in part on the workload of the vascular smooth muscle. These results strongly support the hypothesis that arteriolar walls consume a significant amount of O2 compared with the surrounding tissue. Furthermore, the reduction of vascular tone of arteriolar walls may facilitate an efficient supply of O2 to the surrounding tissue.

scholarly journals Age and sex variation in visceral adipose tissue

2019 ◽  
Vol 6 (1) ◽  
pp. 101
Author(s):  
Pallavi Panchu ◽  
Biju Bahuleyan ◽  
Rose Babu ◽  
Vineetha Vijayan
Keyword(s):  
Adipose Tissue ◽  
Visceral Fat ◽  
Metabolic Disorders ◽  
Age Groups ◽  
Fat Distribution ◽  
Age Group ◽  
Cross Sectional ◽  
Younger Age ◽  
The Difference ◽  
Gender Pattern

Background: Adipose tissue mainly visceral fat is said to be harmful and acts as a harbinger of metabolic disorders. A changing trend is seen in the recent decades with decreasing incidence of metabolic disorders in men even though visceral fat is said to be higher in them. Sex hormones may influence the deposition pattern of adipose tissue. The aim of this study was to observe effects of age on visceral fat and to know if the difference in gender pattern of fat distribution is maintained throughout life or disappears after menopause.Methods: This cross-sectional observational study was conducted in Thrissur on 385 apparently healthy subjects using Omron body composition analyser. Data was analysed using SPSS 20.0 version. The tests employed were NOVA, independent samples t-test.Results: In each age group, men had significantly higher visceral fat than females. As age increased, visceral fat increased significantly in both genders. In each group, except for younger age groups, VF levels were equal in men and women.Conclusions: Visceral fat is higher in men and this difference is seen in all age groups. As age increases, visceral fat levels also increased in men and women. The distribution of visceral fat is such that a greater number of men have high to very high levels at a younger age group, a feature observed in women only in the peri and post-menopausal age. Adoption of an active lifestyle coupled with healthy diet should protect against onset of metabolic disorders.

Vascular manifestations of extensive thermal skin injury in rat mesentery

1964 ◽  
Vol 207 (1) ◽  
pp. 137-143 ◽  
Author(s):  
Leif Horn ◽  
Ole J. Malm
Keyword(s):  
Blood Flow ◽  
Vessel Wall ◽  
Terminal Phase ◽  
Burn Shock ◽  
Red Cell ◽  
Skin Injury ◽  
Cell Agglutination ◽  
Vascular Contractility ◽  
Rat Mesentery ◽  
Mesenteric Microcirculation

After 40% body surface area skin burns, mesenteric microcirculation revealed initially augmented vasomotion and increased epinephrine responsiveness. Lowered precapillary epinephrine thresholds persisted throughout the terminal phase of early fatalities. Animals surviving 48 hr went through a phase with elevated epinephrine thresholds. Venodilatation coexisted with precapillary constriction. Initially most capillaries were empty; a few were dilated and congested with sluggish blood flow, indicating stasis. Lowered epinephrine responsiveness appeared first on the venous side coincident with apparent relief of stasis. Whitish aggregates or "clots" were frequently observed in circulation, but sludging or red cell agglutination was virtually absent. Morphologically the small blood vessels revealed endothelial swelling and there was a tendency for leukocytes to adhere to the vessel wall, the latter feature being more pronounced in later stages of burn shock. Other hemodynamic data indicated general peripheral vasoconstriction which gradually subsided in recovering animals. The circulatory changes are not consistent with circulating "burn toxins" impairing vascular contractility but with disruption of local control of vascular smooth muscle responsiveness, resulting in decompensatory venodilatation.

scholarly journals Genetic Polymorphisms Associated with Spontaneous Intracerebral Hemorrhage

2018 ◽  
Vol 19 (12) ◽  
pp. 3879 ◽  
Author(s):  
Yi-Chun Chen ◽  
Kuo-Hsuan Chang ◽  
Chiung-Mei Chen
Keyword(s):  
Genetic Variation ◽  
Lipid Metabolism ◽  
Intracerebral Hemorrhage ◽  
Genetic Variants ◽  
Vessel Wall ◽  
Current Knowledge ◽  
Gene Variants ◽  
Spontaneous Intracerebral Hemorrhage ◽  
The Difference ◽  
Variance Explained

Differences in the incidence of spontaneous intracerebral hemorrhage (ICH) between ethnicities exist, with an estimated 42% of the variance explained by ethnicity itself. Caucasians have a higher proportion of lobar ICH (LICH, 15.4% of all ICH) than do Asians (3.4%). Alterations in the causal factor exposure between countries justify part of the ethnic variance in ICH incidence. One third of ICH risk can be explained by genetic variation; therefore, genetic differences between populations can partly explain the difference in ICH incidence. In this paper, we review the current knowledge of genetic variants associated with ICH in multiple ethnicities. Candidate gene variants reportedly associated with ICH were involved in the potential pathways of hypertension, vessel wall integrity, lipid metabolism, endothelial dysfunction, inflammation, platelet function, and coagulopathy. Furthermore, variations in APOE (in multiple ethnicities), PMF1/SLC25A44 (in European), ACE (in Asian), MTHFR (in multiple ethnicities), TRHDE (in European), and COL4A2 (in European) were the most convincingly associated with ICH. The majority of the associated genes provide small contributions to ICH risk, with few of them being replicated in multiple ethnicities.

Linear Viscoelastic Behavior of Adipose Tissue

2008 ◽  
Author(s):  
Marion Geerligs ◽  
Gerrit W. M. Peters ◽  
Paul A. J. Ackermans ◽  
Cees W. J. Oomens ◽  
Frank P. T. Baaijens
Keyword(s):  
Adipose Tissue ◽  
Load Transfer ◽  
Numerical Models ◽  
Viscoelastic Behavior ◽  
Needle Insertion ◽  
Surrounding Tissue ◽  
Wide Field ◽  
Linear Viscoelastic Behavior ◽  
Linear Viscoelastic ◽  
Subcutaneous Adipose

Adipose tissue plays an important role in the load transfer between different tissue structures like skin and muscle. Though a plethora of papers can be found on properties of these surrounding tissue layers, only few papers addressed the properties of the adipose layer with its specific morphology. As a result, a thorough constitutive model describing the mechanical behavior of adipose tissue is lacking. This seems odd, because numerical models including the subcutaneous adipose tissue are needed in a wide field of applications such as skin device contact, needle insertion procedures, and understanding deep tissue injuries.

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