scholarly journals Receptor-mediated vascular and metabolic actions of endothelin-1 in canine small intestine

1999 ◽  
Vol 276 (5) ◽  
pp. G1131-G1136 ◽  
Author(s):  
Cheryl E. King-VanVlack ◽  
Jeffrey D. Mewburn ◽  
Christopher K. Chapler
Keyword(s):  
Small Intestine ◽  
Constant Pressure ◽  
Perfusion Pressure ◽  
Venous Blood ◽  
Receptor Blockade ◽  
Endothelin 1 ◽  
A Value ◽  
Anesthetized Dogs ◽  
Group 2 ◽  
Group 1

The effects of endothelin-1 (ET-1) infusion on blood flow (Q˙G) and O2 uptake (V˙o 2G) were examined in the small intestine of anesthetized dogs ( n = 10). Arterial and venous flows of a gut segment were isolated, and the segment was perfused at constant pressure. Arterial and gut venous blood samples were taken, gut perfusion pressure andQ˙G were measured, and O2 extraction ratio (OERG) andV˙o 2Gwere calculated. ET-1 was infused (0.118 μg ⋅ kg−1 ⋅ min−1ia) throughout the experiment. In group 1 ( n = 5), ETA receptors were blocked using BQ-123 (0.143 mg ⋅ kg−1 ⋅ min−1ia) followed by blockade of ETBreceptors with BQ-788 (0.145 mg ⋅ kg−1 ⋅ min−1ia). The order of ETA and ETB receptor blockade was reversed in group 2( n = 5). In group 1, the decrease inQ˙G observed with ET-1 infusion was partially reversed with BQ-123; no further change occurred after BQ-788 administration. In group 2, addition of BQ-788 to the infusate further decreasedQ˙G, whereas addition of BQ-123 returnedQ˙G to a value not different from that with ET-1 infusion alone. These data indicated that ET-1-induced vasoconstriction in the gut was mediated via ETA receptors and that this constriction was buffered by activation of ETB receptors.V˙o 2Gdecreased in proportion to the decrease inQ˙G with ET-1, decreased further with ET-1 plus ETB receptor blockade ( group 2), and increased in proportion to the increases in Q˙Gwith ETA receptor blockade (both groups). No changes in OERGoccurred during ETA and ETB receptor antagonism in either group. This study is the first to demonstrate that a flow-limited decrease in gutV˙o 2Goccurred with infusion of ET-1 in gut vasculature. An intriguing and novel finding was that, during O2limitation, OERG was only 50% of that normally associated with ischemia in this tissue.

Dopamine-1 receptor stimulation impairs intestinal oxygen utilization during critical hypoperfusion

2003 ◽  
Vol 284 (2) ◽  
pp. H668-H675 ◽  
Author(s):  
Jorge A. Guzman ◽  
Ariosto E. Rosado ◽  
James A. Kruse
Keyword(s):  
Blood Flow ◽  
Mucosal Blood Flow ◽  
Control Group ◽  
Oxygen Utilization ◽  
Hemorrhage Control ◽  
Receptor Stimulation ◽  
Anesthetized Dogs ◽  
Group 2 ◽  
Increased Susceptibility ◽  
Group 1

Effects of a dopamine-1 (DA-1) receptor agonist on systemic and intestinal oxygen delivery (D˙o 2)-uptake relationships were studied in anesthetized dogs during sequential hemorrhage. Control ( group 1) and experimental animals ( group 2) were treated similarly except for the addition of fenoldopam (1.0 μg · kg−1 · min−1) in group 2. Both groups had comparable systemic criticalD˙o 2(D˙o 2crit), but animals in group 2 had a higher gut D˙o 2crit(1.12 ± 1.13 vs. 0.80 ± 0.09 ml · kg−1 · min−1, P < 0.05). At the mucosal level, a clear biphasic delivery-uptake relationship was not observed in group 1; thus oxygen consumption by the mucosa may be supply dependent under physiological conditions. Group 2 demonstrated higher peak mucosal blood flow and lack of supply dependency at higher mucosalD˙o 2 levels. Fenoldopam resulted in a more conspicuous biphasic relationship at the mucosa and a rightward shift of overall splanchnic D˙o 2crit despite increased splanchnic blood flow. These findings suggest that DA-1 receptor stimulation results in increased gut perfusion heterogeneity and maldistribution of perfusion, resulting in increased susceptibility to ischemia.

scholarly journals Evaluation of the Accuracy of the Delta Life DL 1000 Oscillometric Monitor for Blood Pressure Measurement in Anesthetized Dogs of Different Weight Ranges

2020 ◽  
Vol 48 ◽  
Author(s):  
Bárbara Silva Correia ◽  
Eduardo Raposo Monteiro ◽  
João Victor Barbieri Ferronatto ◽  
Luciana Branquinho Queiroga ◽  
José Ricardo Herrera Becerra
Keyword(s):  
Blood Pressure ◽  
Arterial Blood Pressure ◽  
Pressure Measurement ◽  
Elective Surgery ◽  
Blood Pressure Measurement ◽  
Measurement Data ◽  
Arterial Blood ◽  
Anesthetized Dogs ◽  
Group 2 ◽  
Group 1

Background: Arterial blood pressure is one of the most commonly variables monitored during anesthetic procedures in veterinary patients. The most reliable method for measuring arterial blood pressure in dogs and cats is the direct (invasive) method. However, the oscillometric method is less complex and more practical for clinical routine in small animals. Nevertheless, oscillometric monitors present great variability in accuracy. The present study aimed to determine the accuracy of the Delta Life DL 1000 oscillometric monitor for measurement of systolic, mean and diastolic blood pressures (SAP, MAP and DAP, respectively) in anesthetized dogs of different weight ranges.Materials, Methods & Results: This study was approved by the Institutional Ethics Committee of Animal Use. Fifteen female dogs of different breeds, weighing 11.6 ± 10.0 kg and with a mean age of 48 ± 51 months were used. All animals were scheduled for elective surgery under general anesthesia in the Institution Veterinary Hospital. Dogs were anesthetized with morphine, propofol and isoflurane and had one 20 or 22 gauge catheter introduced into the dorsal pedal artery for continuous, invasive monitoring of SAP, MAP and DAP. A blood pressure cuff was positioned over the middle third of the radius and connected to Delta Life DL 1000 monitor. Oscillometric readings of SAP, MAP and DAP were registered every 5 minutes, and invasive values were simultaneously recorded. Values obtained with both methods were compared (invasive versus oscillometric) by use of the Bland Altman method to determine the bias, standard deviation of bias and 95% limits of agreement. The percentages of errors between the methods within 10 mmHg and within 20 mmHg were calculated. The results obtained were compared with the criteria from the American College of Veterinary Internal Medicine (ACVIM) for validation of indirect methods of arterial blood pressure measurement. Data were stratified into two groups according to the weight: < 10 kg (Group 1; n = 9); and ≥ 10 kg (Group 2; n = 6). In Group 1, 119 paired measurements were obtained, four of which classified as hypotension (SAP < 90 mmHg), 98 as normotension (SAP from 90 to 140mmHg) and 17 as hypertension (SAP > 140 mmHg). Bias (± SD) values in Group 1 were as follows: SAP, 5.2 ± 18.1 mmHg; MAP, -3.4 ± 17.2 mmHg; and DAP, 12.0 ± 17.5 mmHg. The percentages of errors within 10 mmHg were 40.3% for SAP; 45.4% for MAP and 28.6% for DAP. The percentages of errors within 20 mmHg were 72.3% for SAP, 84.0% for MAP and 68.1% for DAP. In Group 2, 66 paired measurements were obtained, nine of which classified as hypotension, 56 as normotension and one as hypertension. Bias (± SD) in Group 2 were as follows: SAP, 13.6 ± 14.3 mmHg; MAP, -1.1 ± 13.5 mmHg; and DAP, 8.2 ± 16.0 mmHg. The percentages of errors within 10 mmHg were 33.3% for SAP, 77.3% for MAP and 33.3% for DAP. The percentages of errors within 20 mmHg were 65.1% for SAP, 92.4% for MAP and 83.4% for DAP.Discussion: Based on the results of this study and reference criteria from the ACVIM, the Delta Life DL 1000 monitor had a poor accuracy for SAP, MAP and DAP and did not meet the criteria from the ACVIM in anesthetized dogs under 10 kg. Measurements of MAP in dogs ≥ 10 kg met the ACVIM criteria, but measurements of SAP and DAP did not. Based on the findings in this study, the DL 1000 oscillometric monitor is not recommended for blood pressure measurement in anesthetized dogs < 10 kg. In dogs ≥ 10 kg, measurements of MAP yielded acceptable values, but SAP and DAP measurements did not.

Acquired Antithrombin III (AT III) - Deficiency in Septicaemia

1979 ◽  
Author(s):  
E. Deutsch ◽  
E. Thaler
Keyword(s):  
Septic Shock ◽  
Venous Blood ◽  
Heparin Therapy ◽  
Blood Cultures ◽  
Mean Values ◽  
Negative Results ◽  
Significant Difference ◽  
At Iii ◽  
Group 2 ◽  
Group 1

AT III was measured in 34 patients with clinical and bacteriological evidence of septicaemia using a heparin cofactor assay. Based on the results of positive blood cultures gram-negative septicaemia (G-S) was diagnosed in 10 (group 1) and gram positive septicaemia (G+S) in 9 patients (group 2). From the remaining 15 patients {group 3) blood cultures before onset of antibiotic therapy were not obtained and gave negative results throughout the observation period. Based on bacteria] cultures from other sites than venous blood or bacteriological examination of spinal fluid G-S was assumed in 13 and G+S in 2 patients.In all but one patient of group 1 and one of group 2 AT III activities were decreased below 2 SO of normal controls (n = 91, x = 99.6, SD-8.4) already at the time of the first coagulation screening (patients: n=34, =58.4, SD-16.6). Analysis of var-ance showed no significant difference between the mean values of the three groups at the c per cent (%) level. The minimal AT III activities during the course of the disease were below the norma] range in all patients studied [n=34, =51.2, SD=13.6).Thus AT III deficiency appears to be a constant and early finding in G-S and G+S, causing insufficient inhibition of blood coagulation, and hereby may contribute to irreversible tissue damage caused by microthrombi in septic shock. This deficiency may be an important factor in the failure of heparin therapy to reduce mortality from septic shock.

Cardiovascular and renal actions of C-type natriuretic peptide

1992 ◽  
Vol 262 (1) ◽  
pp. H308-H312 ◽  
Author(s):  
A. J. Stingo ◽  
A. L. Clavell ◽  
L. L. Aarhus ◽  
J. C. Burnett
Keyword(s):  
Arterial Pressure ◽  
Natriuretic Peptide ◽  
Sodium Excretion ◽  
Sodium Reabsorption ◽  
Bolus Administration ◽  
Systemic Hemodynamic ◽  
Biological Responses ◽  
Anesthetized Dogs ◽  
Group 2 ◽  
Group 1

Studies were performed in two groups of anesthetized dogs (n = 5 per group) to determine the cardiovascular and renal actions of synthetic C-type natriuretic peptide (CNP). Systemic infusion of CNP (group 1; 10 and 50 ng.kg-1.min-1 iv) resulted in marked cardiovascular hemodynamic effects characterized by a decrease in mean arterial pressure, cardiac output, and atrial pressures in association with a decrease in sodium excretion. Bolus administration of CNP (group 2; 5 micrograms/kg iv) to minimize cardiovascular hemodynamic changes resulted in only a transient decrease in arterial pressure. Sodium excretion decreased despite a return of arterial pressure to baseline. These biological responses were associated with increases in plasma guanosine 3',5'-cyclic monophosphate (cGMP) in both groups but with no change in urinary cGMP. With both systemic infusion or bolus administration of CNP, significant increases in plasma aldosterone were observed in association with increases in distal nephron sodium reabsorption. This study demonstrates that CNP exhibits profound systemic hemodynamic actions and is indirectly, or perhaps directly, antinatriuretic.

A Comparison of Arterial and Venous Flaps

1992 ◽  
Vol 17 (3) ◽  
pp. 359-364 ◽  
Author(s):  
S. P. CHOW ◽  
D. Z. CHEN ◽  
Y. D. GU
Keyword(s):  
Survival Rate ◽  
Elastic Properties ◽  
Perfusion Pressure ◽  
Skin Flap ◽  
Sprague Dawley ◽  
Venous Flaps ◽  
Sprague Dawley Rats ◽  
Group 3 ◽  
Group 2 ◽  
Group 1

The survival rate and elastic properties of the anterior abdominal skin flap in Sprague-Dawley rats were studied in three groups of animals. In group 1 where the flaps were supplied by a normal artery, arterial flaps (1A) had better survival rate and elastic properties than venous flaps (1B). In group 2, where the flaps were supplied by an artery with diminished perfusion pressure, the arterial flaps (2A) still had slightly better results than venous flaps (2B). However, in group 3 where the flaps were supplied by a vein, venous flaps (3B) had better results than arterial flaps (3A).

Differential Effects of Acute and Chronic β-Adrenoreceptor Blockade on Blood Pressure and the Renin—Angiotensin—Aldosterone System in Essential Hypertension

1976 ◽  
Vol 51 (s3) ◽  
pp. 537s-540s
Author(s):  
R. Kolloch ◽  
K. O. Stumpe ◽  
H. Vetter ◽  
W. Gramann ◽  
F. Krück
Keyword(s):  
Blood Pressure ◽  
Essential Hypertension ◽  
Chronic Administration ◽  
Plasma Renin ◽  
Plasma Aldosterone ◽  
Receptor Blockade ◽  
Plasma Aldosterone Concentration ◽  
Group 2 ◽  
Β Receptor ◽  
Group 1

1. Serial measurements of plasma renin activity (PRA), plasma aldosterone concentration (PA) and blood pressure were performed overnight in patients with borderline (group 1) and sustained essential hypertension (group 2) before and after acute and chronic administration of either propranolol or pindolol. 2. Group 1 patients exhibited a typical rhythm of recumbent PRA with low values before midnight and large increases early in the morning. 3. In contrast, no rhythm and very low PRA values were observed in patients of group 2. Blood pressure was higher in group 2 than in group 1. There was a significant correlation between the hyporeninaemic and hypotensive effect of either acute (r = 0·79) or chronic (r = 0·4) β-receptor blockade. 4. In group 1, after β-receptor blockade the day—night profile of renin was similar to that observed in group 2 before treatment. Thus, in this latter subgroup, low-renin profiles might reflect reduced β-adrenoreceptor activity. 5. Plasma aldosterone was lower in group 2 but appeared to be inappropriately high relative to renin. 6. The data suggest that in hypertensive patients classified according to their blood pressure and recumbent PRA profiles a significant relationship exists between changes in PRA and arterial pressure. Thus patients with high PRA respond better to treatment than patients with low renin. We conclude that in the patients studied sympathetic nervous system activity mainly determined renin values as well as anti-hypertensive effectiveness of the β-blocking drugs.

Effects of altered left atrial pressure on pulmonary vascular pressure-flow relationships

1988 ◽  
Vol 255 (1) ◽  
pp. H19-H25 ◽  
Author(s):  
J. Ducas ◽  
U. Schick ◽  
L. Girling ◽  
R. M. Prewitt
Keyword(s):  
Pulmonary Artery ◽  
Pulmonary Artery Pressure ◽  
Pulmonary Vasculature ◽  
Pressure Flow ◽  
Artery Pressure ◽  
Time Control ◽  
Pulmonary Capillary ◽  
Anesthetized Dogs ◽  
Group 2 ◽  
Group 1

We studied the effects of changes in pulmonary capillary wedge pressure (PCWP) on the slope (incremental resistance) and the extrapolated pressure intercept (PI) of the mean pulmonary artery pressure (PAP)-cardiac output (CO) relationship. Multipoint plots of PAP against CO were obtained in intact anesthetized dogs. Group 1 consisted of six dogs entirely in West zone 3 and group 2 of four dogs with mixed West zone 2-3. The four conditions studied were the following: 1) fixed low PCWP, 2) fixed high PCWP, 3) variable PCWP, and 4) time-control repeat of condition 1. The PI significantly exceeded PCWP at fixed low PCWP (group 1, 9.3 vs. 11.1 mmHg, group 2, 6.6 vs. 3.9 mmHg). PI became identical to PCWP only at fixed high PCWP in group 1 (19 +/- 2.0 vs. 19 +/- 1.1 mmHg). Thus PCWP reflects the effective vascular outflow pressure when PCWP is fixed and high. For both groups of dogs in condition 3, when PCWP was varied with CO, the slope of the resulting PAP-CO plot was significantly greater than when PCWP was constant. Also in 9 of 10 dogs, PI was less than PCWP when PCWP was varied. These findings demonstrate that when changes in PCWP are allowed to occur during the generation of a pulmonary artery pressure-flow plot, the resulting slope and intercept, as defined by a Starling resistor model, do not accurately represent the incremental resistance and outflow pressure of the pulmonary vasculature.

Effects of progesterone withdrawal on uterine secretion of prostaglandin F2α in response to oxytocin in ewes

1997 ◽  
Vol 9 (2) ◽  
pp. 255 ◽  
Author(s):  
M. A. Kaminski ◽  
S. H. Hayes ◽  
W. J. Silvia
Keyword(s):  
Venous Blood ◽  
Prostaglandin F2α ◽  
Inhibitory Effect ◽  
Treatment Groups ◽  
Group 4 ◽  
Sham Surgery ◽  
Group 3 ◽  
Group 2 ◽  
Ovine Uterus ◽  
Group 1

Two experiments were conducted to determine if withdrawal of progesterone during the luteal phase of the oestrous cycle affected the ability of the ovine uterus to secrete prostaglandin F2α(PGF2α ) in response to oxytocin. In Experiment 1, 18 ewes were ovariectomized on Day 9 and Day 12 after oestrus. Ewes were subdivided into three treatment groups (n= 6 per group): Group-1 ewes underwent sham surgery; Group-2 ewes received oestradiol (OVX + O); and Group-3 ewes received oestradiol + progesterone (OVX + O,P). Oxytocin was administered to each ewe on Days 10, 13 and 15 after oestrus. Concentrations of 13,14-dihydro-15-keto-PGF2α (PGFM) were determined in samples of jugular venous blood for 2 h after oxytocin challenge. The magnitude of the PGFM response 24 h after ovariectomy was greater (P < 0·1) in ewes from which progesterone had been withdrawn (OVX + O) than in ewes in which progesterone was maintained (intact controls and OVX + O,P). Therefore, progesterone appears to exert an inhibitory effect on uterine secretory responsiveness to oxytocin which is removed by progesterone withdrawal. In Experiment 2, ewes were ovariectomized on Day 11 and assigned to 1 of 4 treatment groups (n = 6 per group): Group 1, no steroid replacement (OVX); Group 2, oestradiol replacement (OVX + O); Group 3, progesterone replacement (OVX + P); or Group 4, progesterone+oestradiol replacement (OVX + O,P). Ewes received oxytocin on Day 12 and Day 15. On Day 12, uterine secretory responsiveness to oxytocin was greatest in ewes in the OVX + O group (P < 0 · 1). Responsiveness was low in ewes in the OVX group, as it was in ewes in both groups that received progesterone replacement. Therefore, the increase in uterine secretory responsiveness to oxytocin following progesterone withdrawal is dependent on oestradiol replacement.

Expression of P-selectin, von Willebrand and endothelin-1 after carotid artery stenting

VASA ◽  
2011 ◽  
Vol 40 (3) ◽  
pp. 199-204 ◽  
Author(s):  
Xia ◽  
Yang ◽  
Qu ◽  
Cheng ◽  
Wang
Keyword(s):  
Carotid Artery ◽  
Carotid Artery Stenting ◽  
Endothelin 1 ◽  
Significant Difference ◽  
Group 2 ◽  
One Year ◽  
Von Willebrand ◽  
The Impact ◽  
Group 1

Background: This study was designed to investigate the impact of carotid artery stenting (CAS) on plasma levels of P-selectin, von Willebrand (vWF) and endothelin-1. Patients and methods: Sixty-seven patients who received CAS were divided into group 1 (one stent for a simple lesion, n = 38) and group 2 (two stents for complex lesions, n = 29). The levels of P-selectin, vWF and endothelin-1 were measured before CAS, 1 h, 6h, 24 h and 2 weeks after the stenting. Results: Sixty-one patients completed one-year follow up. Restenosis was noted in 14 (23 %) patients, among these three (4.8 %) had a restenosis of > 50 % of the vascular lumen. In all patients, the levels of P-selectin, vWF and endothelin-1 increased immediately after CAS (P < 0.05 or < 0.01). The levels of vWF and endothelin-1 in group 2 were higher than in group 1 (P < 0.05 or 0.01). There was no significant difference in P-selectin and endothelin-1 between the restenosis and non-restenosis group (P > 0.05). The 24 h vWF in patients with restenosis were higher than in non-restenosis group (P < 0.05). Conclusions: CAS results in a significant increase in plasma P-selectin, vWF and endothelin-1. The post-CAS levels of P-selectin, vWF and endothelin-1 are related to the extent of endothelial injury. Whether they are associated with restenosis 12 months after the treatment requires further investigation.

scholarly journals Effect of perphenazine on electrogram of rat isolated heart

2011 ◽  
Vol 80 (1) ◽  
pp. 87-92
Author(s):  
Kateřina Fialová ◽  
Jiří Blahák ◽  
Marek Motola ◽  
Jiří Jarkovský ◽  
Jan Mužík ◽  
...  
Keyword(s):  
Heart Rate ◽  
Constant Pressure ◽  
Isolated Heart ◽  
Qtc Prolongation ◽  
Cardiovascular Side Effects ◽  
Male Wistar Rats ◽  
Prolonged Qt ◽  
Group 2 ◽  
Langendorff Hearts ◽  
Group 1

The aim of this study was to clarify whether administration of antipsychotic perphenazine contributes to the electrophysiological changes of the isolated heart. Fourteen adult male Wistar rats were divided into two groups. Langendorff hearts were perfused with Krebs-Henseleit solution at constant pressure (85 mmHg) and 37 °C (CaCl2, 1.2 mM). The electrogram was recorded by touch-free method. The hearts of the first group were exposed to 3.10-5 M perphenazine, the hearts of the second group to 3.10-8 M perphenazine. The incidence of arrhythmias and the heart rate and QT interval changes were studied on electrogram during 30 min periods of control, the first perphenazine administration, washout, and the second drug administration. Perphenazine administration significantly prolonged QT (p < 0.001) and QTc (p < 0.05) in group 1. In group 2, QT and QTc prolongation was less pronounced (p < 0.05). A number of arrhythmias appeared, from single premature ventricular complexes to more severe ones in both groups. The heart rate changes were non-significant. We conclude that although phenothiazines are still medicaments of choice in certain psychoses, their cardiovascular side effects should be always taken in consideration.

Sign in / Sign up

Export Citation Format

Share Document