The velocity of lymph flow in the canine thoracic duct

A method was developed for chronic catheterization of the left thoracic lymph duct at the base of the neck in the sheep fetus, which did not disrupt the other major lymphatic vessels that join the venous circulation at the same location. The lymphatic catheter was connected to a catheter in a jugular vein when lymph flow was not being recorded, so that the lymph continuously returned to the fetal circulation. Special consideration of catheter size to minimize flow resistance and treatment to prevent clotting were required. Individual animals were maintained up to 17 days with lymph flow continuing. In 13 fetuses averaging 128 days gestation (term = 147 days) at the time of catheterization, lymph flow rate was measured for 1 h each day for the first 7 postsurgical days with an on-line computer technique that continuously calculated lymph flow rate. Lymph flow averaged 0.64 +/- 0.17 (SD) ml/min in fetuses weighing 2.3-4 kg and tended to undergo a nonsignificant increase with time. Lymph and plasma protein concentrations did not change with time. In individual fetuses, large spontaneous variations in lymph flow rate occurred over periods of several seconds to a few minutes. Analysis showed that these variations in flow rate were not associated with fetal breathing movements. Thus the present study describes a technique for studying the dynamics of lymph flow in the unanesthetized sheep fetus in utero over a time period limited primarily by the length of gestation. In addition, it appears that thoracic duct lymph flow rate in the fetus per unit body weight averages three to four times that in the adult.

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Thoracic duct lymph flow and protein flux dynamics: responses to intravascular saline

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1981.240.5.r282 ◽

1981 ◽

Vol 240 (5) ◽

pp. R282-R288

Author(s):

R. A. Brace ◽

G. G. Power

Keyword(s):

Thoracic Duct ◽

Fluid Pressure ◽

Nonlinear Function ◽

Lymph Flow ◽

Thoracic Duct Lymph ◽

Plasma Protein Concentration ◽

Flux Dynamics ◽

Before And After ◽

Intravenous Saline ◽

Vascular Compartment

Fluid and protein flux responses in the left thoracic duct and vasculature were measured in pentobarbital-anesthetized, nephrectomized, adult dogs before and after four successive intravascular saline infusions of 2% of body weight each. We found three main characteristics of the thoracic lymph flow and protein flux responses to the intravenous saline: 1) lymph flow reached a peak and then decreased by approximately 40% after each infusion; 2) the maximum lymph flow occurred 5-7 min after terminating each infusion; and 3) the lymph-to-plasma protein concentration ratio fell more than may be expected from the distribution of the infused saline. We were unable to explain these experimental data with a simple two-compartment mathematical model representing the vascular and interstitial spaces. To adequately explain the data, the model had to be expanded to four compartments representing a vascular compartment, two interstitial compartments each with different capillary protein permeabilities, and a lymphatic compartment. We also found it necessary to include interstitial stress relaxation, a nonlinear function curve for lymph flow versus interstitial fluid pressure, and a complaint lymphatic system.

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Chronic lymph flow and transcapillary fluid flux during angiotensin II hypertension

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1990.259.6.r1205 ◽

1990 ◽

Vol 259 (6) ◽

pp. R1205-R1213 ◽

Cited By ~ 1

Author(s):

J. Valenzuela-Rendon ◽

R. D. Manning

Keyword(s):

Angiotensin Ii ◽

Plasma Protein ◽

Thoracic Duct ◽

Protein Transport ◽

Lymph Flow ◽

Fluid Volume ◽

Thoracic Duct Lymph ◽

Ang Ii ◽

Fluid Flux ◽

Duct Lymph

The roles of the transvascular fluid flux and lymph flow in the distribution of extracellular fluid volume during angiotensin II (ANG II) hypertension were evaluated in 11 conscious dogs. Similarly, the factors regulating the distribution of plasma protein across the microvasculature were assessed. By the second day of ANG II infusion, the thoracic duct lymph flow had increased 58% above control, transcapillary fluid flux had increased 45%, and plasma volume, sulfate space, and interstitial fluid volume remained close to control. In addition, the thoracic duct lymph protein transport had increased 34%, and the accompanying increase in transcapillary protein flux prevented any change in plasma protein mass. Also, at this time, the lymph flow and protein transport from subcutaneous tissue in the hind limb were not increased, and the permeability-surface area product of this region decreased 40%. The origin of the increased thoracic duct lymph flow on day 2 probably was from the splanchnic bed. In conclusion, the increased lymph flow during ANG II hypertension compensated for the increase in transcapillary fluid flux, thus preventing edema formation.

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Thoracic duct lymph and lymphocytes during primary hypoxia and rebound

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1965.208.6.1243 ◽

1965 ◽

Vol 208 (6) ◽

pp. 1243-1246 ◽

Cited By ~ 1

Author(s):

D. A. Evans ◽

R. A. F. Garnett ◽

J. M. Yoffey

Keyword(s):

Control Animal ◽

Thoracic Duct ◽

Guinea Pigs ◽

Control Level ◽

Lymph Flow ◽

Total Cell ◽

Thoracic Duct Lymph ◽

Simulated Altitude ◽

Cell Content ◽

Duct Lymph

Thoracic duct lymph flow and lymphocytes were first studied in 18 normal guinea pigs. Similar studies were then made on a) 25 guinea pigs placed in a decompression chamber at a simulated altitude of 14,000 ft for times ranging from 1 to 5 days, this being the period of "primary hypoxia" during which erythropoiesis is stimulated and polycythemia develops, and b) 25 guinea pigs exposed to primary hypoxia for 5 days, then kept in room air for times ranging from 1 to 5 days, this period of posthypoxic polycythemia being known as "rebound." By the end of rebound the polycythemia had almost disappeared. The flow of thoracic duct lymph increased significantly from a control level of 0.86 ± 0.21 ml/hr to 1.23 ± 0.1 ml/hr by the 5th day of primary hypoxia, and to a peak of 1.89 ± 0.23 ml/hr by the 3rd day of rebound, falling slightly to 1.56 ± 0.14 ml/hr by the 5th day of rebound, when it was still markedly above control level. The total cell content of the lymph also rose significantly, from 34.5 ± 10.3 x 106 lymphocytes/hr in the control animal to 59.1 ± 8.9 x 106 /hr on the 5th day of primary hypoxia, and to a peak of 93.8 ± 23.0 x 106 on the 3rd day of rebound.

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