scholarly journals Pharmacokinetics of Nitrate and Nitrite Following Beetroot Juice Drink Consumption

Nutrients ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 281
Author(s):  
Emily Margaret Jakubcik ◽  
Kay Rutherfurd-Markwick ◽  
Marsanne Chabert ◽  
Marie Wong ◽  
Ajmol Ali
Keyword(s):  
Nitric Oxide ◽  
Blood Pressure ◽  
Heart Rate ◽  
Critical Factor ◽  
Beetroot Juice ◽  
Individual Effects ◽  
Bioactive Molecule ◽  
The Individual ◽  
Nitrate And Nitrite

Background: Nitrate (NO3−)-rich beetroot (BR) juice supplementation has been shown to improve cardiovascular function via reduction to nitrite (NO2−) and then to the bioactive molecule nitric oxide (NO). However, limited research exists for the role of inorganic NO2− that is contained naturally within BR. Objective: As BR juice can naturally contain both NO3− and NO2− the objective of this study was to evaluate the individual effects of NO3− and NO2− consumed from BR on plasma [NO3−]/[NO2−] and their subsequent effects on various cardiovascular measures. Design: In four separate treatments, 11 healthy adults consumed 250 mL of BR containing one of the following: (i) high NO3−, low NO2− (HL; 572 mg NO3−, 32 mg NO2−); (ii) medium NO3−, medium NO2− (MM; 280 mg NO3−, 237 mg NO2−); (iii) low NO3−, medium NO2− (LM; 43 mg NO3−, 262 mg NO2−); (iv) placebo (PL; low NO3−, low NO2−: 8 mg NO3−, 5.8 mg NO2−). Plasma [NO3−]/[NO2−], blood pressure, heart rate, mean arterial pressure (MAP), cardiac output and stroke volume were measured at baseline and every hour or second hour for 6 h post-BR consumption. Outcomes: Ingestion of the HL and MM BR increased plasma [NO2−] and [NO3−] after 2 h, with both remaining elevated after 6 h (p < 0.05). LM increased plasma [NO3−] (p < 0.05) but did not increase plasma [NO2−] compared to PL (p = 0.177). MAP was lower following the consumption of HL at 4 h and LM at 6 h (p < 0.05). Conclusion: Inorganic NO3− consumption is the critical factor in elevating plasma [NO3−] and [NO2−]; however, both NO2− and NO3− show potential to reduce MAP. The known reduction of systolic blood pressure (SBP)/diastolic blood pressure (DBP) following NO3− supplementation was not observed, making it unclear if NO2− contributes to a reduction in SBP/DBP alongside NO3−.

Characterization of the role of endogenous nitric oxide in myogenic vascular oscillations during cooling-evoked hemodynamic perturbations of rats

2017 ◽  
Vol 95 (7) ◽  
pp. 803-810 ◽  
Author(s):  
Yi-Hsien Lin ◽  
Yia-Ping Liu ◽  
Yu-Chieh Lin ◽  
Po-Lei Lee ◽  
Che-Se Tung
Keyword(s):  
Nitric Oxide ◽  
Blood Pressure ◽  
Heart Rate ◽  
Cold Stress ◽  
Low Frequency ◽  
Sympathetic Activation ◽  
Nitric Oxide Synthase Inhibitor ◽  
Dicrotic Notch ◽  
Endogenous Nitric Oxide

Rapid immersion of a rat’s limbs into 4 °C water, a model of cold stress, can elicit hemodynamic perturbations (CEHP). We previously reported that CEHP is highly relevant to sympathetic activation and nitric oxide production. This study identifies the role of nitric oxide in CEHP. Conscious rats were pretreated with the nitric oxide synthase inhibitor L-NAME (NG-nitro-l-arginine methyl ester) alone or following the removal of sympathetic influences using hexamethonium or guanethidine. Rats were then subjected to a 10 min cold-stress trial. Hemodynamic indices were telemetrically monitored throughout the experiment. The analyses included measurements of systolic blood pressure; heart rate; dicrotic notch; short-term cardiovascular oscillations and coherence between blood pressure variability and heart rate variability in regions of very low frequency (0.02–0.2 Hz), low frequency (0.2–0.6 Hz), and high frequency (0.6–3.0 Hz). We observed different profiles of hemodynamic reaction between hexamethonium and guanethidine superimposed on L-NAME, suggesting an essential role for a functional adrenal medulla release of epinephrine under cold stress. These results indicate that endogenous nitric oxide plays an important role in the inhibition of sympathetic activation and cardiovascular oscillations in CEHP.

The role of nitric oxide in the development of neurogenic pulmonary edema in spinal cord-injured rats: the effect of preventive interventions

2009 ◽  
Vol 297 (4) ◽  
pp. R1111-R1117 ◽  
Author(s):  
Jiří Šedý ◽  
Josef Zicha ◽  
Jaroslav Kuneš ◽  
Aleš Hejčl ◽  
Eva Syková
Keyword(s):  
Nitric Oxide ◽  
Blood Pressure ◽  
Spinal Cord ◽  
Heart Rate ◽  
Pulmonary Edema ◽  
No Synthase ◽  
Neurogenic Pulmonary Edema ◽  
Therapeutic Effects ◽  
Cord Injury

Neurogenic pulmonary edema (NPE) is an acute life-threatening complication following an injury of the spinal cord or brain, which is associated with sympathetic hyperactivity. The role of nitric oxide (NO) in NPE development in rats subjected to balloon compression of the spinal cord has not yet been examined. We, therefore, pretreated Wistar rats with the NO synthase inhibitor N G-nitro-l-arginine methyl ester (l-NAME) either acutely (just before the injury) or chronically (for 4 wk prior to the injury). Acute (but not chronic) l-NAME administration enhanced NPE severity in rats anesthetized with 1.5% isoflurane, leading to the death of 83% of the animals within 10 min after injury. Pretreatment with either the ganglionic blocker pentolinium (to reduce blood pressure rise) or the muscarinic receptor blocker atropine (to lessen heart rate decrease) prevented or attenuated NPE development in these rats. We did not observe any therapeutic effects of atropine administered 2 min after spinal cord compression. Our data indicate that NPE development is dependent upon a marked decrease of heart rate under the conditions of high blood pressure elicited by the activation of the sympathetic nervous system. These hemodynamic alterations are especially pronounced in rats subjected to acute NO synthase inhibition. In conclusion, nitric oxide has a partial protective effect on NPE development because it attenuates sympathetic vasoconstriction and consequent baroreflex-induced bradycardia following spinal cord injury.

Pre-emptive Analgesia for Postoperative Pain Relief in Children – Role of Paracetamol

2009 ◽  
pp. 9-16
Author(s):  
Rubina Yasmin ◽  
AKM Akhtaruzzaman ◽  
Paresh Chandra Sarker ◽  
Neaz Ahmed ◽  
Ranadhir Kumar Kundu ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Postoperative Pain ◽  
Diclofenac Sodium ◽  
Total Duration ◽  
Pain Scale ◽  
Prospective Clinical Study ◽  
High Dose ◽  
Induction Of Anaesthesia

This prospective clinical study was carried out in the Dept. of Anaesthesia, Analgesia and Intensive Care Medicine, BSMMU, Dhaka, during the period of May 2003 to July 2003. The study was done to emphasize the importance of giving analgesics preemptively instead of waiting for the child to complain of pain and to produce smooth recovery after surgery by decreasing immediate postoperative pain in children by a simple, safe acceptable drug. The children scheduled for tonsillectomy under general anaesthesia were recruited in this study. The analgesic efficiency of rectal paracetamol in two doses, 25 mg/kg bodywt.(Gr-P25) and 50 mg/kg. bodywt. (Gr-P50) were compared with Diclofenac Sodium suppository 1mg/ kg body weight (Gr-D) given half an hour before induction of anaesthesia. Pain scoring was done by TPPPS (Toddler Pre-schooler postoperative pain scale). Heart rate and blood pressure were stable in Gr-P50 and Gr-D. Time of first demand of analgesic was delayed in Gr-P50 and Gr-D. Total paracetamol consumption in 24 hours was less in Gr-P50(181±14.25) and Gr-D (212±25) than Gr-P25(318± 26.39). Total duration of analgesia in Gr- P50 (657±9.94) mins. and in Gr- D(502±10.63) mins. and in Gr-P25(288±23.17) mins. Pre-emptive high dose rectal paracetamol appears to be more effective than diclofenac sodium suppository for postoperative analgesia in children undergoing tonsillectomy. Journal of BSA, Vol. 18, No. 1 & 2, 2005 p.9-16

Systemic and regional hemodynamics after nitric oxide synthase inhibition: role of a neurogenic mechanism

1994 ◽  
Vol 267 (1) ◽  
pp. R84-R88 ◽  
Author(s):  
M. Huang ◽  
M. L. Leblanc ◽  
R. L. Hester
Keyword(s):  
Nitric Oxide ◽  
Blood Pressure ◽  
Cardiac Output ◽  
No Synthase ◽  
Before And After ◽  
Regional Hemodynamics ◽  
Autonomic Blockade ◽  
Infusion Of Norepinephrine ◽  
Oxide Synthase

The study tested the hypothesis that the increase in blood pressure and decrease in cardiac output after nitric oxide (NO) synthase inhibition with N omega-nitro-L-arginine methyl ester (L-NAME) was partially mediated by a neurogenic mechanism. Rats were anesthetized with Inactin (thiobutabarbital), and a control blood pressure was measured for 30 min. Cardiac output and tissue flows were measured with radioactive microspheres. All measurements of pressure and flows were made before and after NO synthase inhibition (20 mg/kg L-NAME) in a group of control animals and in a second group of animals in which the autonomic nervous system was blocked by 20 mg/kg hexamethonium. In this group of animals, an intravenous infusion of norepinephrine (20-140 ng/min) was used to maintain normal blood pressure. L-NAME treatment resulted in a significant increase in mean arterial pressure in both groups. L-NAME treatment decreased cardiac output approximately 50% in both the intact and autonomic blocked animals (P < 0.05). Autonomic blockade alone had no effect on tissue flows. L-NAME treatment caused a significant decrease in renal, hepatic artery, stomach, intestinal, and testicular blood flow in both groups. These results demonstrate that the increase in blood pressure and decreases in cardiac output and tissue flows after L-NAME treatment are not dependent on a neurogenic mechanism.

Increased Pressor Responsiveness to Enkephalin in Spontaneously Hypertensive Rats: The Role of Vasopressin

1980 ◽  
Vol 59 (s6) ◽  
pp. 235s-237s ◽  
Author(s):  
R. W. Rockhold ◽  
J. T. Crofton ◽  
L. Share
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Pressor Response ◽  
Cardiovascular Effects ◽  
Hypertensive Rats ◽  
Methionine Enkephalin ◽  
Spontaneously Hypertensive ◽  
Wistar Kyoto Rats ◽  
Wistar Kyoto

1. The cardiovascular effects of an enkephalin analogue were examined in spontaneously hypertensive and normotensive Wistar-Kyoto rats. (D-Ala2)-methionine enkephalin caused a biphasic increase in blood pressure and an increase in heart rate after intracerebroventricular injection. 2. The initial pressor response to (D-Ala2)-methionine enkephalin was greater in hypertensive than in normotensive rats. No difference was noted between groups during the secondary pressor response. Heart rate increases paralleled the secondary increase in blood pressure. 3. Naloxone pretreatment abolished the secondary increase in blood pressure and the tachycardia, but did not blunt the initial pressor response in female Wistar-Kyoto rats. 4. Plasma levels of arginine vasopressin were depressed during the plateau phase of the pressor response in hypertensive rats given intracerebroventricular (d-Ala2)-methionine enkephalin. 5. The results suggest that the cardiovascular effects of central enkephalin are not due to vasopressin, but may involve activation of the sympathetic nervous system.

scholarly journals Nitric oxide synthase-mediated blood pressure regulation in obese melanocortin-4 receptor-deficient pregnant rats

2016 ◽  
Vol 311 (5) ◽  
pp. R851-R857 ◽  
Author(s):  
Frank T. Spradley ◽  
Jennifer M. Sasser ◽  
Jacqueline B. Musall ◽  
Jennifer C. Sullivan ◽  
Joey P. Granger
Keyword(s):  
Nitric Oxide ◽  
Blood Pressure ◽  
Mesenteric Arteries ◽  
Elevated Blood Pressure ◽  
Pressure Regulation ◽  
Elevated Blood ◽  
Pregnant Rats ◽  
Melanocortin 4 Receptor ◽  
Regulation Of Blood Pressure

Although obesity increases the risk for hypertension in pregnancy, the mechanisms responsible are unknown. Increased nitric oxide (NO) production results in vasodilation and reduced blood pressure during normal pregnancy in lean rats; however, the role of NO is less clear during obese pregnancies. We examined the impact of obesity on NO synthase (NOS)-mediated regulation of blood pressure during pregnancy by testing the hypothesis that NOS activity, expression, and regulation of vascular tone and blood pressure are reduced in obese pregnant rats. At gestational day 19, melanocortin-4 receptor (MC4R)-deficient obese rats (MC4R) had greater body weight and fat mass with elevated blood pressure and circulating sFlt-1 levels compared with MC4R pregnant rats. MC4R pregnant rats also had less circulating cGMP levels and reduced total NOS enzymatic activity and expression in mesenteric arteries. Despite decreased biochemical measures of NO/NOS in MC4R rats, NOS inhibition enhanced vasoconstriction only in mesenteric arteries from MC4R rats, suggesting greater NOS-mediated tone. To examine the role of NOS on blood pressure regulation in obese pregnant rats, MC4R and MC4R pregnant rats were administered the nonselective NOS inhibitor NG-nitro-l-arginine methyl ester (l-NAME, 100 mg/l) from gestational day 14 to 19 in drinking water. The degree by which l-NAME raised blood pressure was similar between obese and lean pregnant rats. Although MC4R obese pregnant rats had elevated blood pressure associated with reduced total NOS activity and expression, they had enhanced NOS-mediated attenuation of vasoconstriction, with no evidence of alterations in NOS-mediated regulation of blood pressure.

Leukocyte kinetics in the human lung: role of exercise and catecholamines

1984 ◽  
Vol 57 (3) ◽  
pp. 711-719 ◽  
Author(s):  
A. L. Muir ◽  
M. Cruz ◽  
B. A. Martin ◽  
H. Thommasen ◽  
A. Belzberg ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Peripheral Blood ◽  
Human Lung ◽  
Work Load ◽  
Low Flow ◽  
Epinephrine Infusion ◽  
First Pass ◽  
Pass Through

In six normal supine subjects epinephrine infusion produced a greater leukocytosis with smaller changes in heart rate and blood pressure than did norepinephrine or isoproterenol. Upright exercise in those subjects produced a greater leukocytosis than supine exercise at the same work load. To determine the lung's participation in these events, indium-labeled neutrophils (PMN) were given to four of the subjects. We found that 20–25% were retained in the first pass through the lung when compared with technetium-labeled erythrocytes. The number of labeled PMN in the lung gradually decreased and the number in the spleen and the liver increased. Exercise and catecholamine infusion caused an acceleration in the release of labeled cells from the lung, an increase in both labeled and unlabeled cells in the peripheral blood, and an increase in the number of labeled cells in the liver and spleen. This suggests that increased perfusion of low-flow areas in the lung may contribute to the increased leukocytosis seen in association with both exercise and catecholamine infusion.

Role of Screening Tests in the Detection and Management of Blood Pressure Abnormalities Among Young Population

Angiology ◽  
2016 ◽  
Vol 68 (5) ◽  
pp. 441-446 ◽  
Author(s):  
Mehmet Karaduman ◽  
Mustafa Aparci ◽  
Murat Unlu ◽  
Cengiz Ozturk ◽  
Sevket Balta ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Cardiovascular Disease ◽  
Body Mass Index ◽  
Heart Rate ◽  
Medical Records ◽  
Screening Tests ◽  
Young Population ◽  
Males And Females ◽  
Apparently Healthy

The prevalence of hypertension is increasing among young population worldwide. So there is an interest in detecting prehypertension and hypertension in childhood. We determined blood pressure (BP) recorded at a screening test in a young population. We retrospectively evaluated the medical records including systolic blood pressure (SBP), diastolic blood pressure (DBP), weight, height, and body mass index (BMI) of 685 male and 130 female apparently healthy adolescents. We evaluated the prevalence of BP categories: normotension, prehypertension, and hypertension. The prevalence of normotension (n = 369), prehypertension (n = 333), and hypertension (n = 113) was 45.3%, 40.9% and 13.9%, respectively; prehypertension and hypertension were significantly higher among males. The prevalence of prehypertension and hypertension was significantly higher among overweight males and females. The BMI significantly correlated with SBP, DBP, and heart rate among both genders. The prevalence of prehypertension and hypertension is high among Turkish adolescents. Screening tests focused on BP and BMI measurement may help detect the young population at risk of hypertension and cardiovascular disease in the future.

Renal denervation alters cardiovascular and endocrine responses to hemorrhage in conscious newborn lambs

1998 ◽  
Vol 275 (1) ◽  
pp. H285-H291 ◽  
Author(s):  
Francine G. Smith ◽  
Isam Abu-Amarah
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Renal Denervation ◽  
Plasma Renin ◽  
Sympathetic Nerves ◽  
Renal Nerves ◽  
Elevated Plasma ◽  
Baseline Levels ◽  
Renal Sympathetic

To investigate the role of renal sympathetic nerves in modulating cardiovascular and endocrine responses to hemorrhage early in life, we carried out three experiments in conscious, chronically instrumented lambs with intact renal nerves (intact; n = 8) and with bilateral renal denervation (denervated; n = 5). Measurements were made 1 h before and 1 h after 0, 10, and 20% hemorrhage. Blood pressure decreased transiently after 20% hemorrhage in intact lambs and returned to control levels. In denervated lambs, however, blood pressure remained decreased after 60 min. After 20% hemorrhage, heart rate increased from 170 ± 16 to 207 ± 18 beats/min in intact lambs but not in denervated lambs, in which basal heart rates were already elevated to 202 ± 21 beats/min. Despite an elevated plasma renin activity (PRA) measured in denervated (12.0 ± 6.4 ng ANG I ⋅ ml−1 ⋅ h−1) compared with intact lambs (4.0 ± 1.1 ng ANG I ⋅ ml−1 ⋅ h−1), the increase in PRA in response to 20% hemorrhage was similar in both groups. Plasma levels of arginine vasopressin increased from 11 ± 8 to 197 ± 246 pg/ml after 20% hemorrhage in intact lambs but remained unaltered in denervated lambs from baseline levels of 15 ± 10 pg/ml. These observations provide evidence that in the newborn, renal sympathetic nerves modulate cardiovascular and endocrine responses to hemorrhage.

Sign in / Sign up

Export Citation Format

Share Document