Comparison of vascular response of different locations of the gastrointestinal tract to isoproterenol and nifedipine

1990 ◽  
Vol 68 (12) ◽  
pp. 1563-1567 ◽  
Author(s):  
I. Prokopiw ◽  
P. K. Dinda ◽  
I. T. Beck
Keyword(s):  
Blood Flow ◽  
Gastrointestinal Tract ◽  
Channel Blocker ◽  
Axillary Artery ◽  
Regional Blood Flow ◽  
The Body ◽  
Receptor Density ◽  
Ascending Colon ◽  
Similar Increase ◽  
Vascular Response

In the present study we have compared the effect of intravenous infusion of a calcium channel blocker, nifedipine (1.0 μg∙kg−1∙min−1 for 20 min), with that of isoproterenol (0.1 μg∙kg−1∙min−1 for 20 min) on the hemodynamic parameters and the vascular response of different locations and tissue layers of the gastrointestinal tract. Heart rate increased with isoproterenol but not with nifedipine. Both agents caused a similar increase in cardiac output and a similar fall in mean arterial pressure. After 20 min infusion, nifedipine increased the blood flow of the axillary artery, but isoproterenol had no such effect. Isoproterenol caused vasodilation of the mucosa in the antrum but not in the fundus and the body of the stomach or in the duodenum, jejunum, mid small intestine, ileum, and colon. The mucosal effect of nifedipine was similar, except that it also caused vasodilation in the small bowel and in the ascending colon. Nifedipine caused vasodilation of the muscularis throughout the gastrointestinal tract, but isoproterenol had no such effect. These differences are discussed in relation to the mechanism of action of these two vasodilators. It is suggested that the vascular response of different locations and tissue layers of the gastrointestinal tract to vasodilators is locally regulated by a variety of mechanisms. These mechanisms may include β- and α-receptor density and (or) sensitivity, angiotensin II activity, and metabolic need of the tissues.Key words: nifedipine, isoproterenol, regional blood flow, microspheres, hemodynamics.

Regional blood flow measurement in vivo for a definable geometry

1964 ◽  
Vol 206 (5) ◽  
pp. 962-966 ◽  
Author(s):  
Marvin B. Bacaner ◽  
James S. Beck
Keyword(s):  
Blood Flow ◽  
Flow Measurement ◽  
Necessary Conditions ◽  
Regional Blood Flow ◽  
The Body ◽  
Continuous Measure ◽  
Radioisotope Method ◽  
Arterial Concentration ◽  
Regional Concentration

A radioisotope method for measuring regional blood flow in the intestine of the dog in vivo has been favorably compared with measurement by timed collection of total venous outflow. The necessary conditions are a continuous measure of arterial concentration and cumulative regional concentration of radioisotope, an experimentally definable region, and temporary complete retention of tracer. The derivation of the relations used suggests additional applications of the method to other regions of the body.

scholarly journals Solitary Plasmacytoma of the Cecum and the Ascending Colon: Surgical Resection as a Treatment Modality

2015 ◽  
Vol 2015 ◽  
pp. 1-4 ◽  
Author(s):  
Tahsin Dalgic ◽  
Erdal Birol Bostanci ◽  
Tebessum Cakir ◽  
Ilter Ozer ◽  
Murat Ulas ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Gastrointestinal Tract ◽  
Rare Disease ◽  
Surgical Resection ◽  
Treatment Modality ◽  
The Body ◽  
Resected Specimen ◽  
Solitary Plasmacytoma ◽  
Ascending Colon ◽  
Adequate Treatment

Colonic solitary plasmacytoma is a rare disease, with few reports occurring in the literature. Solitary plasmacytoma is defined as a plasma cell tumour with no evidence of bone marrow infiltration. Plasmacytoma can present as a solitary tumour in bone or in other parts of the body. The gastrointestinal tract is rarely the site of the disease. We report on the case of a 51-year-old man presenting with a colonic symptomatic mass with unclear biopsy results. A resected specimen showed a solitary plasmacytoma. Surgical resection was an adequate treatment modality in this case. Endoscopic resection, radiotherapy, and chemotherapy are also preferred treatments in selected gastrointestinal plasmacytoma cases.

Effect of Ciclosporin on Cardiac Output and Regional Blood Flow in Rats: Ciclosporin-lnduced Nephropathy and Its Prevention with Calcium Channel Blocker

Nephron ◽  
1992 ◽  
Vol 61 (2) ◽  
pp. 204-210 ◽  
Author(s):  
T. Kishimoto ◽  
T. Tsujino ◽  
T. Nakatani ◽  
T. Kim ◽  
A. Ohyama ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Calcium Channel ◽  
Calcium Channel Blocker ◽  
Channel Blocker ◽  
Regional Blood Flow

Blood flow in different areas of the gastrointestinal tract in the anesthetized dog

1969 ◽  
Vol 47 (9) ◽  
pp. 787-790 ◽  
Author(s):  
Bernard Goodhead
Keyword(s):  
Blood Flow ◽  
Gastrointestinal Tract ◽  
Gall Bladder ◽  
Regional Blood Flow ◽  
Sodium Pentobarbital ◽  
Ideal Tracer

Radioactive rubidium (86Rb) acts as the almost ideal tracer and gives accurate measurements of regional blood flow. In dogs weighing between 10 and 20 kg and anesthetized with sodium pentobarbital, blood was distributed to the various gastrointestinal organs as follows: esophagus 29.5 ml/min 100 g; stomach 52.3 ml/min 100 g; gall bladder 35.8 ml/min 100 g; duodenum 111.1 ml/min 100 g; pancreas 65.2 ml/min 100 g; jejunum and ileum 99.5 ml/min 100 g; and colon 123.6 ml/min 100 g.

Cardiovascular System: Part II

2019 ◽  
Author(s):  
Vanetta Levesque
Keyword(s):  
Blood Flow ◽  
Blood Volume ◽  
Hormonal Regulation ◽  
Blood Circulation ◽  
Venous Return ◽  
Regional Blood Flow ◽  
The Body ◽  
Venous Capacitance ◽  
System Part ◽  
The Right

This chapter gives an overview of blood circulation, then focuses on regional blood flow to a number of organs, and ends with a description of the microcirculation. It begins with venous return and blood volume. Most blood volume is contained within the venous system, and the chapter describes several mechanisms that allow for this volume of blood to be returned to the right heart. Next it describes the various means by which the blood circulation and volume are controlled. The chapter devotes considerable time describing the central, peripheral, and hormonal regulation of circulation and blood volume. Next, regional blood flow is described. Blood flow in different regions of the body is usually autoregulated, and variably controlled by the autonomic nervous system, and various humoral agents. The final section describes the mechanism by which blood flow in the microcirculation delivers nutrients, and removes wastes from the tissue by diffusion. Also described are the regulation of the microcirculation by pre and post capillary sphincters, and the effect of viscosity. This review contains 5 figures, and 40 references.  Keywords: venous return, vascular compliance, venous capacitance, vasomotor center, hypothalamic-pituitary-adrenal axis (HPA), microcirculation, regional blood flow, mixed venous oxygen saturation

scholarly journals Is intercompartmental urea clearance during hemodialysis a perfusion term? A comparison of two pool urea kinetic models.

1995 ◽  
Vol 6 (5) ◽  
pp. 1360-1370
Author(s):  
D Schneditz ◽  
B Fariyike ◽  
R Osheroff ◽  
N W Levin
Keyword(s):  
Blood Flow ◽  
Cell Membrane ◽  
Membrane Permeability ◽  
Flow Model ◽  
Regional Blood Flow ◽  
The Body ◽  
Membrane Model ◽  
Cell Membrane Permeability ◽  
Cell Membrane Model ◽  
Blood Flow Model

Analyses of intradialytic and postdialytic urea profiles call for models that consider delayed urea transfer from different parts of the body to the blood. There are two different approaches to the problem. In the classical cell membrane model it is assumed that the two compartments refer to the serial (s) arrangement of extracellular and intracellular volumes, whereas in the regional blood flow model the two compartments are identified as parallel (p) organ systems with high or low perfusion. In the cell membrane model, delayed urea removal from peripheral body compartments is governed by intercompartmental clearance (Kc) which is a function of cell membrane permeability, whereas in the regional blood flow model delayed urea removal is related to low perfusion (QL) of the large muscle/skin/bone compartment. Both models were compared in a set of 16 high-efficiency hemodialysis treatments. Modeled volumes (Vm,s = 31.2 +/- 9.5 L; Vm,p = 30.0 +/- 8.3 L) and modeled dose of hemodialysis (Kt/Vm,s = Kt/Vm,p = 1.12 +/- 0.33) were the same for both models. However, volumes modeled by either technique were significantly lower than anthropometric volumes (V alpha = 35.0 +/- 6.4 L). These data suggest that at this point the two models are experimentally indistinguishable. Moreover, the main system parameters of both models, Kc (0.54 +/- 0.16 L/min) and QL (0.63 +/- 0.15 L/min) showed a strong linear dependence (QL = 0.921 Kc + 0.139, r2 = 0.884), whereas no relation could be found between Kc and Vm. Therefore, delayed transport that has up to now been characterized by membrane permeability may also be explained by peripheral perfusion.

Regional Blood Flow by Fractional Distribution of Indicators

1958 ◽  
Vol 193 (1) ◽  
pp. 161-168 ◽  
Author(s):  
Leo A. Sapirstein
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Regional Blood Flow ◽  
The Body ◽  
Arterial System ◽  
Whole Body ◽  
Blood Concentrations ◽  
Arterial Blood ◽  
The Brain ◽  
Fractional Uptake

K42 Cl, Rb86Cl and iodoantipyrine (I131) were given in single intravenous injections to rats. The isotope content of the organs and the arterial blood concentrations were studied as a function of time. K42Cl and Rb86Cl reached a stable level in all organs other than the brain in 6–9 seconds and maintained this level until 64 seconds. The arterial concentration curves for the isotopes showed that the injected dose was almost completely transferred into the arterial system at about 6–8 seconds. The isotopes showed subsequent recirculation amounting to about 40% of the original dose between the first recirculation and 64 seconds. The organs which displayed stability during the period of recirculation must have had extraction ratios from zero time less than 1.00 but equal to that of the whole body. The fractional uptake of indicator by such organs must therefore have been equal to their blood flow fraction of the cardiac output. The brain reached its maximum content of Rb86 and K42 in 5–6 seconds; both isotopes then disappeared rapidly. The brain was thus shown to have a lower extraction ratio toward these isotopes than the body as a whole; its flow fraction could not therefore be measured by their use. Most organs failed to show stability of their iodoantipyrine content between 9 and 64 seconds; this indicator is not suitable for the measurement of the flow fraction of such organs. By combining values for the cardiac output and the fractional uptake of K42 in dog organs, regional blood flow values were obtained. For those other organs where flow values by other methods are available, the agreement was good. The following blood flow values were obtained in the major organs of the dog: Heart (coronary flow), 1.0 ml/gm/min.; kidney, 3.0 ml/gm/min.; liver, 1.2 ml/gm/min. (0.4 ml/gm/min. hepatic artery, 0.8 ml/gm/min. portal vein); skin, 0.07 ml/gm/min.

Assessment of the incorporation of revascularized fibula grafts used for mandibular reconstruction with F-18-PET

2001 ◽  
Vol 40 (02) ◽  
pp. 51-58 ◽  
Author(s):  
H. Schliephake ◽  
van den Hoff ◽  
W. H. Knapp ◽  
G. Berding
Keyword(s):  
Blood Flow ◽  
Regional Blood Flow ◽  
Venous Blood ◽  
Mandibular Reconstruction ◽  
Reference Region ◽  
Osteoblastic Activity ◽  
Non Union ◽  
Range Of Values ◽  
Measured Input

Summary Aim: Determination of the range of regional blood flow and fluoride influx during normal incorporation of revascularized fibula grafts used for mandibular reconstruction. Evaluation, if healing complications are preceded by typical deviations of these parameters from the normal range. Assessment of the potential influence of using “scaled population-derived” instead of “individually measured” input functions in quantitative analysis. Methods: Dynamic F-l 8-PET images and arterialized venous blood samples were obtained in 11 patients early and late after surgery. Based on kinetic modeling regional blood flow (K1) and fluoride influx (Kmlf) were determined. Results: In uncomplicated cases, early postoperative graft K1 - but not Kmlf -exceeded that of vertebrae as reference region. Kmn values obtained in graft necrosis (n = 2) were below the ranges of values observed in uncomplicated healing (0.01 13-0.0745 ml/min/ml) as well as that of the reference region (0.0154-0.0748). Knf values in mobile non-union were in the lower range - and those in rigid non-union in the upper range of values obtained in stable union (0.021 1-0.0694). If scaled population-derived instead of measured input functions were used for quantification, mean deviations of 23 ± 17% in K1 and 12 ± 16% in Kmlf were observed. Conclusions: Normal healing of predominantly cortical bone transplants is characterized by relatively low osteoblastic activity together with increased perfusion. It may be anticipated that transplant necrosis can be identified by showing markedly reduced F− influx. In case that measured input functions are not available, quantification with scaled population-derived input functions is appropriate if expected differences in quantitative parameters exceed 70%.

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