scholarly journals Insights of posture dependent pressure characteristics in five rats

2021 ◽  
Vol 7 (2) ◽  
pp. 799-802
Author(s):  
Fabian Flürenbrock ◽  
Simone Schwander ◽  
Anthony Podgoršak ◽  
Britta Bausch ◽  
Petra Seebeck ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Radio Telemetry ◽  
Pressure Fluctuations ◽  
Relevant Information ◽  
Quantitative Model ◽  
Csf Dynamics ◽  
Femoral Blood ◽  
Freely Moving ◽  
Excessive Accumulation ◽  
Current Shunt

Abstract Current shunt treatments of hydrocephalus, a condition characterized by excessive accumulation of cerebrospinal fluid (CSF) and intracranial pressure (ICP) fluctuations, suffer malfunctions caused by changes in patient’s posture. Research toward a quantitative model describing posture dependent dynamics of CSF related pressures such as ICP and blood pressure (BP) shall provide relevant information that can lead to a better understanding of CSF dynamics and thus, improved treatment outcomes. In this pilot study, ICP and femoral blood pressure (FBP) were measured concurrently in anaesthetized as well as awake and freely moving rats using radio telemetry. It was shown that despite the inherent challenges of limited space for sensor implants and rapid movements leading to strong artefacts, influences on CSF related pressure fluctuations due to posture changes can be observed in individual rats

scholarly journals Telemetric monitoring of blood pressure in freely moving mice: a preliminary study

2000 ◽  
Vol 34 (3) ◽  
pp. 272-280 ◽  
Author(s):  
Klaas Kramer ◽  
Hans-Peter Voss ◽  
Joop A. Grimbergen ◽  
Perry A. Mills ◽  
Daniel Huetteman ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Data Acquisition ◽  
Radio Telemetry ◽  
Ambient Pressure ◽  
Measurement Techniques ◽  
Systolic Pressure ◽  
Data Acquisition System ◽  
Acquisition System ◽  
Absolute Pressure ◽  
Freely Moving

This paper describes for the first time the possibility for recording the systolic pressure (SPI, diastolic pressure (DP), and the mean arterial pressure (MAP) as well as the heart rate (HR) and locomotor activity (LA) in freely moving mice, using a commercially available telemetry and data acquisition system. The system comprises a new, small radio-telemetry transmitter implanted in the peritoneal cavity, a receiver board placed underneath the home cage, a multiplexer and a computer-based data acquisition system. The signals from the receiver were consolidated by the multiplexer and were stored and analysed by the computer. The telemetered pressure signals (absolute pressure) were corrected automatically for changes in atmospheric pressure measured by an ambient pressure monitor. The effects of implantation on animal behaviour, and, after the animals had recovered, the effects of handling on the SP, DP, MAP and HR were examined. The radio-telemetry system for recording the SP, DP, MAP and HR provides an accurate and reliable method for monitoring the direct effects of handling on SP, DP, MAP and HR. In addition, by using this new blood pressure (BP) transmitter, we maintain that BP measurements in freely moving mice are more efficient, reliable, and less labour-intensive than the measurement techniques described in the literature thus far.

Cardiac baroreflex dysfunction in patients with pulmonary arterial hypertension at rest and during orthostatic stress: Role of the peripheral chemoreflex

2021 ◽  
Author(s):  
Marcelle Paula-Ribeiro ◽  
Indyanara C. Ribeiro ◽  
Liliane C. Aranda ◽  
Talita M. Silva ◽  
Camila M. Costa ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Early Stage ◽  
Pressure Fluctuations ◽  
Sit To Stand ◽  
Peak Aerobic Capacity ◽  
Pulmonary Arterial ◽  
Peripheral Chemoreflex

The baroreflex integrity in early-stage pulmonary arterial hypertension (PAH) remains uninvestigated. A potential baroreflex impairment could be functionally relevant and possibly mediated by enhanced peripheral chemoreflex activity. Thus, we investigated 1) the cardiac baroreflex in non-hypoxemic PAH; 2) the association between baroreflex indexes and peak aerobic capacity (i.e., V̇O2peak); and 3) the peripheral chemoreflex contribution to the cardiac baroreflex. Nineteen patients and 13 age- and sex-matched healthy adults (HA) randomly inhaled either 100% O2 (peripheral chemoreceptors inhibition) or 21% O2 (control session), while at rest and during a repeated sit-to-stand maneuver. Beat-by-beat analysis of R-R intervals and systolic blood pressure provided indexes of cardiac baroreflex sensitivity (cBRS) and effectiveness (cBEI). The PAH group had lower cBEIALL at rest (mean ± SD: PAH = 0.5 ± 0.2 vs HA = 0.7 ± 0.1 a.u., P = 0.02) and lower cBRSALL (PAH = 6.8 ± 7.0 vs HA = 9.7 ± 5.0 ms mmHg-1, P < 0.01) and cBEIALL (PAH = 0.4 ± 0.2 vs HA= 0.6 ± 0.1 a.u., P < 0.01) during the sit-to-stand maneuver versus the HA group. The cBEI during the sit-to-stand maneuver was independently correlated to V̇O2peak (partial r = 0.45, P < 0.01). Hyperoxia increased cBRS and cBEI similarly in both groups at rest and during the sit-to-stand maneuver. Therefore, cardiac baroreflex dysfunction was observed under spontaneous and, most notably, provoked blood pressure fluctuations in non-hypoxemic PAH, was not influenced by the peripheral chemoreflex, and was associated with lower V̇O2peak suggesting it could be functionally relevant.

Sympathetic Nerve Activity-Induced Blood Pressure Fluctuations are Stacked on Linearly: A Simulation Study

2018 ◽  
Vol 50 (4) ◽  
pp. 243-248
Author(s):  
W. T. Tseng ◽  
W. C. Shann ◽  
B. C. Chen ◽  
Y. C. Chang ◽  
M. L. Tsai
Keyword(s):  
Blood Pressure ◽  
Simulation Study ◽  
Sympathetic Nerve ◽  
Sympathetic Nerve Activity ◽  
Pressure Fluctuations ◽  
Nerve Activity

Abstract 291: Antihypertensive Effect Of Bia 5-1058 a New Selective Peripheral Dopamine β-hydroxylase Inhibitor

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Bruno Igreja ◽  
Nuno M Pires ◽  
Lyndon C Wright ◽  
Patrío Soares-da-Silva
Keyword(s):  
Blood Pressure ◽  
Nervous System ◽  
Sympathetic Nervous System ◽  
Receptor Antagonist ◽  
Antihypertensive Effect ◽  
Antihypertensive Drugs ◽  
Radio Telemetry ◽  
Sympathetic Nerves ◽  
Maximum Reduction ◽  
Sympathetic Nervous

The sympathetic nervous system can alter blood pressure by modulation of cardiac output, peripheral vascular resistance and renal function. One strategy for controlling sympathetic nerve function is to reduce the biosynthesis of norepinephrine (NE) via inhibition of dopamine β-hydroxylase (DβH; EC 1.14.17.1 ), the enzyme that catalyses the conversion of dopamine (DA) to NE in sympathetic nerves. BIA 5-1058 is a reversible DβH inhibitor that decreases NE levels in peripheral sympathetically innervated tissues slowing down sympathetic nervous system drive, without effect in brain tissues. In freely moving SHR implanted with radio-telemetry transmitters single administration of BIA 5-1058 showed a dose (3, 30 and 100 mg/Kg) and time dependent effect on blood pressure with no significant effect on heart rate (HR) and total activity monitored over a 96-hour period. The maximum reduction on systolic blood pressure (SBP) was -10.8, -21.1 and -35.2 mmHg for 3, 30 and 100 mg/Kg, respectively and the maximum reduction on diastolic blood pressure (DBP) was -9.9, -18.4 and -24.8 mmHg for 3, 30 and 100 mg/Kg, respectively. The antihypertensive effect of BIA 5-1058 (30 mg/Kg) was further evaluated in combination with efficacious doses of well-known antihypertensive drugs, like the ACE inhibitor captopril, the AT1 receptor antagonist losartan, the diuretic hydrochlorothiazide, beta-blocker metoprolol, the alpha-1 receptor antagonist prazosin, and the calcium channel blocker diltiazem. All drugs were administered orally (single dose) in a cross-over design and the effect was monitored for 72 hours. The combination of BIA 5-1058 with any of the tested antihypertensive drugs caused a stronger and prolonged blood pressure decrease than any of the compounds alone.In conclusion, peripheral DβH inhibitors can be used, alone or in combination with others antihypertensive drugs, to reduce blood pressure.

scholarly journals Associations between arterial stiffness and blood pressure fluctuations after spinal cord injury

Spinal Cord ◽  
2019 ◽  
Vol 57 (12) ◽  
pp. 1057-1063 ◽  
Author(s):  
Katharine D. Currie ◽  
Michèle Hubli ◽  
Maureen J. MacDonald ◽  
Andrei V. Krassioukov
Keyword(s):  
Blood Pressure ◽  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Arterial Stiffness ◽  
Pressure Fluctuations ◽  
Cord Injury

scholarly journals Blood Pressure Instability in Persons With SCI: Evidence From a 30-Day Home Monitoring Observation

2019 ◽  
Vol 32 (10) ◽  
pp. 938-944 ◽  
Author(s):  
Caitlyn G Katzelnick ◽  
Joseph P Weir ◽  
April Jones ◽  
Marinella Galea ◽  
Trevor A Dyson-Hudson ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Medical Center ◽  
Pressure Fluctuations ◽  
Home Monitoring ◽  
Extended Period ◽  
Blood Pressure Monitor ◽  
Pressure Monitor ◽  
Cord Injury

Abstract Background To determine the degree of blood pressure instability over a 30-day home observation in participants with spinal cord injury grouped by level of injury pertaining to cardiovascular autonomic regulation. Methods This is an observational study completed at the Kessler Foundation and James J. Peters Veterans Medical Center. Seventy-two participants with tetraplegia (C1–T1), 13 with high thoracic (T2–T4), and 28 with low thoracic (T5–T12) injury participated in this study. Participants were asked to record their blood pressure using an ambulatory blood pressure monitor three times a day for 30 days. Results The number of blood pressure fluctuations was significantly increased in the tetraplegia group compared with the paraplegia groups. Age and duration of injury contributed to an increase in the observation of 30-day blood pressure instability; however, completeness of injury did not. Conclusion The data indicate significant blood pressure instability that may not be exclusive to persons with tetraplegia; in fact, individuals with low thoracic injuries demonstrated severe blood pressure fluctuations. The use of a monitor at home for an extended period may help document dangerous and extreme fluctuations in blood pressure and should be considered an important adjunctive clinical practice for tracking of the secondary consequences in the spinal cord injury population.

Sign in / Sign up

Export Citation Format

Share Document