Evaluation of the Time Course of Vascular Responses to Venous Congestion in the Human Lower Limb

Lymphedema is manifested as a chronic swelling arising due to stasis in the lymphatic flow. No cure is currently available. A non-invasive treatment is a 3 week complete decongestive therapy (CDT), including manual lymphatic drainage and compression bandaging to control swelling. As CDT leads to mobilization of several liters of fluid, effects of CDT on hyaluronan clearance (maker for lymphatic outflow), volume regulating hormones, total plasma protein as well as plasma density, osmolality and selected electrolytes were investigated. In this pilot study, we assessed hyaluronan and volume regulating hormone responses from plasma samples of nine patients (three males, six females, aged 55 ± 13 years) with lower limb lymphedema stage II-III, before - and after - CDT. A paired non-parametric test (Wilcoxon) was used to assess hormonal and plasma volume changes. Correlation was tested using Spearman’s correlation. The main findings of this novel study are that lymphedema patients lost volume and weight after therapy. Hyaluronic acid did not significantly change pre- compared to post-CDT. Aldosterone increased significantly after therapy, while plasma renin activity increased, but not significantly. Plasma total protein, density, osmolality and sodium and chloride did not show differences after CDT. To our knowledge, no study has previously investigated the effects of CDT on volume regulating hormones or electrolytes. To identify the time-course of volume regulating hormones and lymphatic flow changes induced by CDT, future studies should assess these parameters serially over 3 weeks of therapy.

Download Full-text

Tuning of a Basic Coordination Pattern Constructs Straight-Ahead and Curved Walking in Humans

Journal of Neurophysiology ◽

10.1152/jn.00817.2003 ◽

2004 ◽

Vol 91 (4) ◽

pp. 1524-1535 ◽

Cited By ~ 96

Author(s):

Grégoire Courtine ◽

Marco Schieppati

Keyword(s):

Principal Components ◽

Lower Limb ◽

Time Course ◽

Body Movement ◽

The Body ◽

Whole Body ◽

Coordination Pattern ◽

Data Set ◽

Coordination Patterns ◽

Straight Ahead

We tested the hypothesis that common principles govern the production of the locomotor patterns for both straight-ahead and curved walking. Whole body movement recordings showed that continuous curved walking implies substantial, limb-specific changes in numerous gait descriptors. Principal component analysis (PCA) was used to uncover the spatiotemporal structure of coordination among lower limb segments. PCA revealed that the same kinematic law accounted for the coordination among lower limb segments during both straight-ahead and curved walking, in both the frontal and sagittal planes: turn-related changes in the complex behavior of the inner and outer limbs were captured in limb-specific adaptive tuning of coordination patterns. PCA was also performed on a data set including all elevation angles of limb segments and trunk, thus encompassing 13 degrees of freedom. The results showed that both straight-ahead and curved walking were low dimensional, given that 3 principal components accounted for more than 90% of data variance. Furthermore, the time course of the principal components was unchanged by curved walking, thereby indicating invariant coordination patterns among all body segments during straight-ahead and curved walking. Nevertheless, limb- and turn-dependent tuning of the coordination patterns encoded the adaptations of the limb kinematics to the actual direction of the walking body. Absence of vision had no significant effect on the intersegmental coordination during either straight-ahead or curved walking. Our findings indicate that kinematic laws, probably emerging from the interaction of spinal neural networks and mechanical oscillators, subserve the production of both straight-ahead and curved walking. During locomotion, the descending command tunes basic spinal networks so as to produce the changes in amplitude and phase relationships of the spinal output, sufficient to achieve the body turn.

Download Full-text

A novel technique to study the time course of morphological and functional vascular responses to hypertension in conscious rats

The FASEB Journal ◽

10.1096/fasebj.24.1_supplement.786.15 ◽

2010 ◽

Vol 24 (S1) ◽

Author(s):

Harald Martin Stauss ◽

Katie M Leick ◽

Jason W Burkle ◽

Diane L Rotella ◽

Kevin R Rarick ◽

...

Keyword(s):

Time Course ◽

Vascular Responses ◽

Conscious Rats ◽

Novel Technique

Download Full-text

Differential effect of taurocholic acid on hepatic arterial resistance vessels and bile flow

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1983.244.4.g366 ◽

1983 ◽

Vol 244 (4) ◽

pp. G366-G369 ◽

Cited By ~ 1

Author(s):

W. W. Lautt ◽

T. R. Daniels

Keyword(s):

Hepatic Artery ◽

Bile Flow ◽

Time Course ◽

Parenchymal Cell ◽

Taurocholic Acid ◽

Metabolic Effects ◽

Vascular Effects ◽

Bile Formation ◽

Liver Parenchymal Cell ◽

Vascular Responses

The "hepatic arterial buffer response" hypothesis states that the hepatic artery is not controlled by liver parenchymal cell metabolic activity. Bile salts stimulate liver metabolism (elevate bile formation) and dilate the hepatic artery. The present data show that the vascular and metabolic effects in cats anesthetized with pentobarbital sodium are independent. Low doses of taurocholate (1 microM . min-1 . kg-1) produce metabolic but not vascular responses. At higher doses both the hepatic artery and superior mesenteric artery dilate with equal sensitivity. Taurocholate into the portal vein produced elevated bile flow and hepatic arterial dilation; infusion via the hepatic artery resulted in equal metabolic responses but much greater vascular effects. In addition, the time course of onset and termination of the metabolic and vascular responses supports the conclusion that the effects of taurocholic acid on hepatic bile flow and hepatic arterial flow are independent actions. This adds further support for the hepatic arterial buffer response being controlled by factors other than local hepatic metabolic demands.

Download Full-text

Time course of changes in upper and lower limb vasodilatory reserve and exercise capacity after recovery from chronic heart failure

Journal of Cardiac Failure ◽

10.1016/s1071-9164(99)91148-x ◽

1999 ◽

Vol 5 (3) ◽

pp. 45

Author(s):

Naoshi Arakawa ◽

Motoyuki Nakamura ◽

Junya Kamata ◽

Shoma Sugawara ◽

Kenji Ueshima ◽

...

Keyword(s):

Heart Failure ◽

Chronic Heart Failure ◽

Exercise Capacity ◽

Lower Limb ◽

Time Course

Download Full-text

Vascular responses to venous congestion.

Journal of Applied Physiology ◽

10.1152/jappl.1967.22.5.889 ◽

1967 ◽

Vol 22 (5) ◽

pp. 889-899 ◽

Cited By ~ 3

Author(s):

R L Walker ◽

I F Mackay ◽

P Van Loon

Keyword(s):

Venous Congestion ◽

Vascular Responses

Download Full-text

Arterial distensibility: acute changes following dynamic exercise in normal subjects

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00529.2002 ◽

2003 ◽

Vol 284 (3) ◽

pp. H970-H978 ◽

Cited By ~ 64

Author(s):

Katerina K. Naka ◽

Ann C. Tweddel ◽

Dimitris Parthimos ◽

Andrew Henderson ◽

Jonathan Goodfellow ◽

...

Keyword(s):

Blood Pressure ◽

Lower Limb ◽

Time Course ◽

Vascular Tone ◽

Normal Subjects ◽

Large Artery ◽

Arterial Distensibility ◽

Linear Differential ◽

Acute Changes ◽

Response To Exercise

The time course of acute changes in large artery distensibility immediately and for 60 min following maximum treadmill exercise in normal subjects was characterized by simultaneously measuring upper and lower limb pulse wave velocity (PWV). A new oscillometric technique was used, which has proven to be sensitive to changes in distensibility induced by acute changes in vascular tone independently of blood pressure. The observed changes in PWV are attributable to changes in vascular tone corresponding to recovery from a systemic net constrictor response and a local net dilator response to exercise with persisting postexercise vasodilatation. They are inadequately explained by associated changes in blood pressure and cannot be attributed to changes in heart rate or viscosity. Modeled as a system of n coupled linear differential equations, the minimum (and adequate) order required to reproduce these patterns was n = 1 for the upper and n = 2 for the exercising lower limb. The economy of the solution suggests entrainment among the multiple interactive mechanisms governing vasomotor control.

Download Full-text

A novel technique to study the time course of morphological and functional vascular responses to hypertension in conscious rats

10.17077/etd.652djqd4 ◽

2010 ◽

Author(s):

Katie Leick

Keyword(s):

Time Course ◽

Vascular Responses ◽

Conscious Rats ◽

Novel Technique

Download Full-text

Effect of Endothelin on the Function of the Isolated Perfused Working Rat Heart

Clinical Science ◽

10.1042/cs0790221 ◽

1990 ◽

Vol 79 (3) ◽

pp. 221-226 ◽

Cited By ~ 18

Author(s):

J. D. Firth ◽

A. F. C. Roberts ◽

A. E. G. Raine

Keyword(s):

Cardiac Output ◽

Rat Heart ◽

Time Course ◽

Calcium Entry ◽

Calcium Entry Blockers ◽

High Concentration ◽

Vascular Responses ◽

Coronary Vasoconstriction ◽

Working Rat Heart ◽

Sustained Increase

1. The effect of endothelin on the performance of the isolated perfused working rat heart has been examined. 2. A low concentration of endothelin (60 pmol/l) produced a gradual but sustained increase in cardiac output; coronary vascular resistance was unaffected. 3. A high concentration of endothelin (600 pmol/l) produced a rapid increase in cardiac output, followed by a marked fall in cardiac output as progressive, severe coronary vasoconstriction developed. 4. The coronary vasoconstriction induced by endothelin (600 pmol/l) was partially blocked by nicardipine (0.5 pmol/l) 5. In the presence of either nicardipine (0.5 μmol/l) or verapamil (0.2 μmol/l), the increment in cardiac output induced by endothelin (600 pmol/l) was greater than that induced by the addition of the same concentration of endothelin to hearts which had not been exposed to calcium-entry blockers. 6. The effect of endothelin on myocardial contractility has a different time course, concentration dependence and response to calcium-entry blockade than the effect on the coronary vasculature. This suggests that different mechanisms are involved in the generation of the myocardial and vascular responses to endothelin.

Download Full-text

Changes in brachial artery endothelial function and resting diameter with moderate-intensity continuous but not sprint interval training in sedentary men

Journal of Applied Physiology ◽

10.1152/japplphysiol.00058.2017 ◽

2017 ◽

Vol 123 (4) ◽

pp. 773-780 ◽

Cited By ~ 12

Author(s):

Ninette Shenouda ◽

Jenna B. Gillen ◽

Martin J. Gibala ◽

Maureen J. MacDonald

Keyword(s):

Endothelial Function ◽

Brachial Artery ◽

Lower Limb ◽

Time Course ◽

Interval Training ◽

Moderate Intensity ◽

Sprint Interval Training ◽

Peripheral Artery ◽

Continuous Training ◽

Healthy Men

Moderate-intensity continuous training (MICT) improves peripheral artery function in healthy adults, a phenomenon that reverses as continued training induces structural remodeling. Sprint interval training (SIT) elicits physiological adaptations similar to MICT, despite a lower exercise volume and time commitment; however, its effect on peripheral artery function and structure is largely unexplored. We compared peripheral artery responses to 12 wk of MICT and SIT in sedentary, healthy men (age = 27 ± 8 yr). Participants performed MICT (45 min of cycling at 70% peak heart rate; n = 10) or SIT (3 × 20-s “all out” cycling sprints with 2 min of recovery; n = 9), and responses were compared with a nontraining control group (CTL, n = 6). Allometrically scaled brachial flow-mediated dilation (FMD) increased 2.2% after 6 wk of MICT and returned to baseline levels by 12 wk, but did not change in SIT or CTL (group × time interaction, P = 0.04). Brachial artery diameter increased after 6 and 12 wk (main effect, P = 0.03), with the largest increases observed in MICT. Neither training protocol affected popliteal relative FMD and diameter, or central and lower limb arterial stiffness (carotid distensibility, central and leg pulse wave velocity) ( P > 0.05 for all). Whereas earlier and more frequent measurements are needed to establish the potential presence and time course of arterial responses to low-volume SIT, our findings suggest that MICT was superior to the intense, but brief and intermittent SIT stimulus at inducing brachial artery responses in healthy men. NEW & NOTEWORTHY We compared the effects of 12 wk of moderate-intensity continuous training (MICT) and sprint interval training (SIT) on peripheral artery endothelial function and diameter, and central and lower limb stiffness in sedentary, healthy men. Whereas neither training program affected the popliteal artery or stiffness indexes, we observed changes in brachial artery function and diameter with MICT but not SIT. Brachial artery responses to SIT may follow a different time course or may not occur at all.

Download Full-text