scholarly journals The effect of a 48 h fast on the physiological responses to food ingestion in normal-weight women

1990 ◽  
Vol 63 (1) ◽  
pp. 53-64 ◽  
Author(s):  
I. W. Gallen ◽  
I. A. Macdonald ◽  
P. I. Mansell
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Metabolic Rate ◽  
Diastolic Blood Pressure ◽  
Test Meal ◽  
Forearm Blood Flow ◽  
Physiological Responses ◽  
Normal Weight ◽  
Plasma Catecholamine ◽  
Food Ingestion

The thermogenic, cardiovascular and metabolic responses to a 30 kJ/kg body-weight test meal were studied in eight normal-weight, healthy female subjects after a 6 or 48 h fast. There was no significant change in metabolic rate following the 48 h fast, but plasma glucose, insulin, noradrenaline and respiratory exchange ratio were all reduced, and plasma β-hydroxybutyrate was increased. Forearm blood flow was increased, with reduction in diastolic blood pressure. After the 48 h fast, there was a reduction in the metabolic rate response 40–90 min after food (control+0·54 (se0·05), 48 h fast + 0·27 (se0·12) kJ/min,I< 0·01), and in forearm blood flow and diastolic blood pressure responses, but increases in heart rate, blood glucose and plasma insulin responses to the ingestion of the test meal. There was no significant relationship between plasma catecholamine concentration and food ingestion or metabolic rate. Fasting induced considerable adaptation in these subjects and altered some of the physiological responses to food ingestion.

scholarly journals The cardiovascular, metabolic and hormonal changes accompanying acute starvation in men and women

1994 ◽  
Vol 71 (3) ◽  
pp. 437-447 ◽  
Author(s):  
J. Webber ◽  
I. A. Macdonald
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Metabolic Rate ◽  
Respiratory Exchange Ratio ◽  
Forearm Blood Flow ◽  
Plasma Catecholamines ◽  
Plasma Metabolites ◽  
Hormonal Changes ◽  
Plasma Adrenaline ◽  
Acute Starvation

The effect of fasting for 12, 36 and 72 h was studied in twenty-nine healthy subjects (seventeen women and twelve men). Measurements were made of cardiovascular variables, metabolic rate, respiratory exchange ratio, plasma metabolites, insulin, thyroid hormones and catecholamines. During starvation there were no significant changes in blood pressure, whilst heart rate (beatslmin) increased at 36 h and remained elevated after 72 h (12 h 625 (SE 1.8), 36 h 68.0 (SE 1.9), 72 h 69 2 (SE 1.8);P< 0.001). Forearm blood flow(FBF),increased progressively from 3.32 (SE 0.20) to 6.21(SE0.46) m1/100 ml per min (P< 0.001). Resting metabolic rate (kJ/min) was significantly increased after 36 h of starvation (12 h 4 60 (SE 0.14), 36 h 4 88 (SE 0.13),P< 0.001), but was not significantly different from the 12 h value after 72 h (72 h 4.72(SE0.15)P= 0.06). The respiratory exchange ratio fell progressively from 0.80 to 076 to 0.72 (P< 0.001). Blood glucose fell, whilst plasma glycerol and β-hydroxybutyrate rose and plasma lactate did not change. Plasma insulin and free triiodothyronine fell during starvation. Plasma adrenaline and noradrenaline were unchanged at 36 h, but were significantly increased after 72 h. Both sexes showed a similar pattern of response to starvation, although absolute values of blood pressure, forearm blood flow, metabolic rate and plasma catecholamines were higher in men than women. Acute starvation produces profound cardiovascular and metabolic changes which are not explained by the accompanying hormonal changes.

Lutein Complex Supplementation Increases Ocular Blood Flow Biomarkers in Healthy Subjects

2019 ◽  
Vol 89 (1-2) ◽  
pp. 5-12
Author(s):  
Alon Harris ◽  
Brent Siesky ◽  
Amelia Huang ◽  
Thai Do ◽  
Sunu Mathew ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Diastolic Blood Pressure ◽  
Healthy Subjects ◽  
Ocular Blood Flow ◽  
Capillary Blood ◽  
Post Treatment ◽  
Capillary Blood Flow ◽  
Doppler Imaging ◽  
Retinal Capillary

Abstract. Introduction: To investigate the effects of a lutein complex supplementation on ocular blood flow in healthy subjects. Materials and Methods: Sixteen healthy female patients (mean age 36.8 ± 12.1 years) were enrolled in this randomized, placebo-controlled, double-blinded, two-period crossover study. Subjects received daily an oral dose of the lutein with synergistic phytochemicals complex (lutein (10 mg), ascorbic acid (500 mg), tocopherols (364 mg), carnosic acid (2.5 mg), zeaxanthin (2 mg), copper (2 mg), with synergistic effects in reducing pro-inflammatory mediators and cytokines when administered together in combination) and placebo during administration periods. Measurements were taken before and after three-week supplementation periods, with crossover visits separated by a three-week washout period. Data analysis included blood pressure, heart rate, intraocular pressure, visual acuity, contrast sensitivity detection, ocular perfusion pressure, confocal scanning laser Doppler imaging of retinal capillary blood flow, and Doppler imaging of the retrobulbar blood vessels. Results: Lutein complex supplementation produced a statistically significant increase in mean superior retinal capillary blood flow, measured in arbitrary units (60, p = 0.0466) and a decrease in the percentage of avascular area in the superior (−0.029, p = 0.0491) and inferior (−0.023, p = 0.0477) retina, as well as reduced systolic (−4.06, p = 0.0295) and diastolic (−3.69, p = 0.0441) blood pressure measured in mmHg from baseline. Data comparison between the two supplement groups revealed a significant decrease in systemic diastolic blood pressure (change from pre- to post-treatment with lutein supplement (mean (SE)): −3.69 (1.68); change from pre- to post-treatment with placebo: 0.31 (2.57); p = 0.0357) and a significant increase in the peak systolic velocity (measured in cm/sec) in the central retinal artery (change from pre- to post-treatment with lutein supplement: 0.36 (0.19); change from pre- to post-treatment with placebo: −0.33 (0.21); p = 0.0384) with lutein complex supplement; data analyses from the placebo group were all non-significant. Discussion: In healthy participants, oral administration of a lutein phytochemicals complex for three weeks produced increased ocular blood flow biomarkers within retinal vascular beds and reduced diastolic blood pressure compared to placebo.

Forearm and finger blood flow responses to passive body tilts

1979 ◽  
Vol 46 (2) ◽  
pp. 288-292 ◽  
Author(s):  
Y. A. Mengesha ◽  
G. H. Bell
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Arterial Blood Pressure ◽  
Vascular Resistance ◽  
Pulse Rate ◽  
Forearm Blood Flow ◽  
Body Tilt ◽  
Finger Blood Flow ◽  
Arterial Blood ◽  
Forearm Vascular Resistance

Ten to fifteen healthy subjects, ages 18--30 yr, were used to assess the correlation of forearm blood flow with graded passive body tilts and vascular resistance and also to discern the relative effects of body tilts on finger blood flow. In the head-up tilts forearm blood flow and arterial blood pressure fell progressively, whereas forearm vascular resistance and pulse rate increased. In the head-down tilts the forearm blood flow and the arterial blood pressure increased, whereas the forearm vascular resistance and pulse rate decreased. These changes were found to be significantly correlated with the different tilt angles and with one another. In a preliminary study it was found that infrared heating of the carpometacarpal region produced finger vasodilatation similar to the forearm vasodilatation observed by Crockford and Hellon (6). However, unlike forearm blood flow, finger blood flow showed no appreciable response to either the head-up or head-down tilts. This indicates that the sympathetic tone and the volume of blood in the finger are not appreciably altered by this test procedure at least 1 min after the body tilt is assumed.

Effect of the Ace Inhibitor Ceronapril on Cerebral Blood flow in Hypertensive Patients

1996 ◽  
Vol 30 (6) ◽  
pp. 578-582 ◽  
Author(s):  
Neal R Cutler ◽  
John J Sramek ◽  
Azucena Luna ◽  
Ismael Mena ◽  
Eric P Brass ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Diastolic Blood Pressure ◽  
Arterial Blood Pressure ◽  
Mean Arterial Blood Pressure ◽  
Enzyme Inhibitor ◽  
Blood Pressure Response ◽  
Combined Therapy ◽  
Arterial Blood

Objective To assess the effect of the angiotensin-converting enzyme inhibitor ceronapril on cerebral blood flow (CBF) in patients with moderate hypertension. Design Patients received chlorthalidone 25 mg for 4 weeks, and if diastolic blood pressure remained in the range of 100–115 mm Hg, they were given titrated doses of ceronapril (10–40 mg/d based on blood pressure response) in addition to chlorthalidone for 9 weeks. Setting Outpatient research clinic. Subjects Eligible patients had moderate essential hypertension (diastolic blood pressure 100–115 mm Hg) assessed when the patients were receiving no medications. Thirteen patients were entered into the study; 1 withdrew for reasons unrelated to the study drug. Twelve patients (11 men, 1 woman; mean age 52 y) completed the study. Intervention Ceronapril, given with chlorthalidone. Main Outcome Measures CBF measurements were taken at the start and end of ceronapril therapy using intravenous 133Xe; blood pressures were determined weekly. Results Mean arterial blood pressure decreased from 130 ± 4 to 120 ±7 mm Hg after 4 weeks of chlorthalidone administration, and fell further to 108 ± 8 mm Hg after an additional 9 weeks of combined chlorthalidone-ceronapril therapy (p < 0.05). CBF fell from 44 ± 15 to 34 ± 5 mL/min/100 g during the 9 weeks of combined therapy (p = 0.05). No adverse effects consistent with decreased CBF were observed. The decrease in CBF was not linearly correlated with the change in systemic blood pressure, but was strongly correlated (r = –0.937; p < 0.001) with the initial CBF. Conclusions The decrease in mean arterial blood pressure was not associated with a decrease in CBF. Patients with high CBF may be predisposed to a decrease in CBF when treated with ceronapril and chlorthalidone.

Temperature Biofeedback Training to Improve Peripheral Blood Flow in the Upper Extremities of Diabetic Patients

1984 ◽  
Vol 51 (5) ◽  
pp. 219-224 ◽  
Author(s):  
Elizabeth Dean
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Diastolic Blood Pressure ◽  
Peripheral Blood ◽  
Diabetic Group ◽  
Biofeedback Training ◽  
Control Group ◽  
Diabetic Patients ◽  
Peripheral Blood Flow ◽  
Temperature Biofeedback

Ten control and ten diabetic subjects were first given a baseline session of no temperature biofeedback, and then were exposed to four 40-minute temperature biofeedback sessions over consecutive days. As the result of feedback training, peripheral skin temperatures increased on the training (right) hands of both groups, and this occurred to a greater extent in the diabetic group. Concomitant temperature increases occurred also in the left hands of both groups. Neither group produced any significant changes in heart rate, respiration rate, or systolic blood pressure with the exception of a significant decrease in diastolic blood pressure for the diabetic group. No difference in diastolic blood pressure was observed, however, when the diabetics were compared with the control group. The results would suggest further evaluation of temperature biofeedback training is warranted in a diabetic population as a potential means of increasing peripheral blood flow in the extremities.

scholarly journals Cardiovascular Effects of Sedative Infusions of Propofol and Midazolam after Spinal Anaesthesia

1988 ◽  
Vol 16 (3) ◽  
pp. 292-298 ◽  
Author(s):  
D. W. Blake ◽  
G. Donnan ◽  
J. Novella ◽  
C. Hackman
Keyword(s):  
Blood Pressure ◽  
Diastolic Blood Pressure ◽  
Spinal Anaesthesia ◽  
Forearm Blood Flow ◽  
Recovery Period ◽  
Cardiovascular Effects ◽  
Pelvic Surgery ◽  
Control Group ◽  
Intravenous Sedation ◽  
The Difference

The cardiovascular effects of intravenous sedation were studied in fifty patients after spinal anaesthesia for lower limb or pelvic surgery. Twenty patients received propofol (mean dosage 74 (SD 4) μg/kg/min for 0–20 minutes and 51 (SD 7) μg/kg/min for 20–40 minutes), twenty received midazolam (35 μg/kg + 2.54 (SD 0.2) μg/kg/min for 0–20 minutes and 1.35 (SD 0.2) μg/kg/min for 20–40 minutes) and ten patients received saline infusion only. The forearm vasoconstriction in response to the spinal anaesthesia was measured by strain gauge plethysmography. Spinal anaesthesia lowered systolic and diastolic blood pressure by 18 (SED 4) mmHg and 9 (SED 2) mmHg respectively. (SED = standard error of the difference.) This was associated with a 32% decrease in mean forearm blood flow. Propofol and midazolam caused similar additional reductions in systolic and diastolic blood pressure (10 (SED 4) mmHg and 4 (SED 2) mmHg) and a decrease in heart rate (P< 0.005), but forearm vasoconstriction was not altered. In the control group, however, forearm vasoconstriction increased during 40 minutes in theatre (P<0.05). Recovery from propofol was far more rapid than after midazolam and was virtually complete in ten minutes. This was reflected by an increase in blood pressure and in forearm vasoconstriction in the recovery period.

Effects of caffeine on blood pressure, heart rate, and forearm blood flow during dynamic leg exercise

1998 ◽  
Vol 85 (1) ◽  
pp. 154-159 ◽  
Author(s):  
Jason W. Daniels ◽  
Paul A. Molé ◽  
James D. Shaffrath ◽  
Charles L. Stebbins
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Flow ◽  
Systolic Blood Pressure ◽  
Skin Temperature ◽  
Rectal Temperature ◽  
Forearm Blood Flow ◽  
Dynamic Exercise ◽  
Ang Ii ◽  
Leg Exercise

This study examined the acute effects of caffeine on the cardiovascular system during dynamic leg exercise. Ten trained, caffeine-naive cyclists (7 women and 3 men) were studied at rest and during bicycle ergometry before and after the ingestion of 6 mg/kg caffeine or 6 mg/kg fructose (placebo) with 250 ml of water. After consumption of caffeine or placebo, subjects either rested for 100 min (rest protocol) or rested for 45 min followed by 55 min of cycle ergometry at 65% of maximal oxygen consumption (exercise protocol). Measurement of mean arterial pressure (MAP), forearm blood flow (FBF), heart rate, skin temperature, and rectal temperature and calculation of forearm vascular conductance (FVC) were made at baseline and at 20-min intervals. Plasma ANG II was measured at baseline and at 60 min postingestion in the two exercise protocols. Before exercise, caffeine increased both systolic blood pressure (17%) and MAP (11%) without affecting FBF or FVC. During dynamic exercise, caffeine attenuated the increase in FBF (53%) and FVC (50%) and accentuated exercise-induced increases in ANG II (44%). Systolic blood pressure and MAP were also higher during exercise plus caffeine; however, these increases were secondary to the effects of caffeine on resting blood pressure. No significant differences were observed in heart rate, skin temperature, or rectal temperature. These findings indicate that caffeine can alter the cardiovascular response to dynamic exercise in a manner that may modify regional blood flow and conductance.

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