Denne side blev automatisk oversat, og nøjagtigheden af ​​oversættelsen er ikke garanteret. Der henvises til engelsk version for en kildetekst.

The Role of Endothelin in the Supine Hypertension of Autonomic Failure

27. september 2021 opdateret af: Italo Biaggioni, Vanderbilt University
The purpose of this study is to test the hypothesis that endothelin plays a role in the pathogenesis of supine hypertension in pure autonomic failure by increasing vascular resistance. To gauge its contribution to blood pressure regulation, pure autonomic failure and multiple system atrophy patients with supine hypertension will undergo a medication testing with the endothelin blocker, BQ123. We will compare the hemodynamic effects between PAF and MSA patients. Our primary endpoint will be the decrease in blood pressure during the administration of this compound.

Studieoversigt

Status

Trukket tilbage

Betingelser

Intervention / Behandling

Detaljeret beskrivelse

The pathophysiologic mechanisms causing supine hypertension in patients with autonomic failure are not completely understood.In MSA patients, supine hypertension may be explained by residual sympathetic tone, possibly acting on hypersensitive adrenoreceptors and unstrained by the lack of baroreflex modulation. In contrast, the pathogenesis of hypertension in PAF remains unknown. Hypertension in these patients is not related to intravascular volume, residual sympathetic tone, or renin mechanisms. Increased vascular resistance is the underlying hemodynamic mechanism. The driving force of this increased vascular tone, however, is not known.

We hypothesize that endothelin (ET)-l contributes to the increased vascular resistance in pure autonomic failure patients with supine hypertension. To gauge its contribution to blood pressure regulation, we will induce endothelin blockade with acute systemic administration of BQ123 in an ascending dose regimen (25, 50, 100 and 300 nmol/min) and we will compare the hemodynamic effects between PAF and MSA patients.

Subjects will be studied on 3 different days, one with saline (placebo) and two with BQ123: a 'low dose' day (25 and 50 nmol/min infusions separated by 75 min) and a 'high dose' day (100 and 300 nmol/min infusions separated by 75 min). The order of the placebo day will be randomized in a single-blinded manner so that each subject receives it on a different visit. The order of the BQ123 study days will be always the same, starting with the low dose. If SBP drops by >40 mm Hg or SBP < 130 mm Hg during the monitoring period after the first or second infusion, the following dose(s) of BQ123 will not be given and patients will receive normal saline until the study ends.

Ganglionic Blockade with Trimethaphan (optional study day):

The purpose of this study day is to determine the level of residual sympathetic tone that contributes to supine hypertension in each autonomic failure patient by inducing transient withdrawal of the autonomic nervous system. This approach would allow us to identify patients in whom supine hypertension is not driven by sympathetic tone and thus, better characterize the role of endothelin in the hypertension of these patients.

Undersøgelsestype

Interventionel

Fase

  • Fase 1

Kontakter og lokationer

Dette afsnit indeholder kontaktoplysninger for dem, der udfører undersøgelsen, og oplysninger om, hvor denne undersøgelse udføres.

Studiesteder

  • Forenede Stater
    • Tennessee
      • Nashville, Tennessee, Forenede Stater, 37232
        • Vanderbilt University

Deltagelseskriterier

Forskere leder efter personer, der passer til en bestemt beskrivelse, kaldet berettigelseskriterier. Nogle eksempler på disse kriterier er en persons generelle helbredstilstand eller tidligere behandlinger.

Berettigelseskriterier

Aldre berettiget til at studere

18 år til 85 år (Voksen, Ældre voksen)

Tager imod sunde frivillige

Ingen

Køn, der er berettiget til at studere

Alle

Beskrivelse

Inclusion Criteria:

  • Patients with autonomic failure and supine hypertension from all races, who are in the hospital participating in the study "The Evaluation and Treatment of Autonomic Failure" (IRB# 000814).
  • Supine hypertension, defined as a systolic blood pressure >150 mm Hg or diastolic blood pressure > 90 mm Hg.
  • Males and females, between 18-85yr.
  • Provide written informed consent to participate in the study and understand that they may withdraw their consent at any time without prejudice to their future medical care.

Exclusion Criteria:

  • Pregnant women.
  • High-risk patients (e.g. heart failure, symptomatic coronary artery disease, liver impairment, history of stroke or myocardial infarction).
  • History of serious allergies or asthma.
  • In the investigator's opinion, have clinically significant abnormalities on clinical, mental examination or laboratory testing.
  • All medical students.

Studieplan

Dette afsnit indeholder detaljer om studieplanen, herunder hvordan undersøgelsen er designet, og hvad undersøgelsen måler.

Hvordan er undersøgelsen tilrettelagt?

Design detaljer

  • Primært formål: Andet
  • Tildeling: Randomiseret
  • Interventionel model: Crossover opgave
  • Maskning: Enkelt

Våben og indgreb

Deltagergruppe / Arm
Intervention / Behandling
Eksperimentel: BQ123
endothelin blocker
Medicin: BQ123
Low dose day: 25 nmol/min, single IV infusion for 15 min.
Andre navne:
  • BQ-123 sodium salt
Medicin: BQ123
Low dose day: 50 nmol/min, single IV infusion for 15 min
Andre navne:
  • BQ-123 sodium salt
Medicin: BQ123
High dose day: 300 nmol/min, single IV infusion for 15 min.
Andre navne:
  • BQ-123 sodium salt
Placebo komparator: Saline
IV saline
Medicin: Saline
2-3 IV saline infusions for 15 min each.
Andre navne:
  • Normal saline, 0.9% sodium chloride

Hvad måler undersøgelsen?

Primære resultatmål

Resultatmål
Foranstaltningsbeskrivelse
Tidsramme
Change in Systolic BP
Tidsramme: 0 -4 hr post infusion
Change from baseline in systolic blood pressure
0 -4 hr post infusion

Sekundære resultatmål

Resultatmål
Foranstaltningsbeskrivelse
Tidsramme
Change in cardiac output, stroke volume and systemic vascular resistance
Tidsramme: 0-4 hr post infusion
Percent change from baseline in hemodynamic parameters
0-4 hr post infusion

Samarbejdspartnere og efterforskere

Det er her, du vil finde personer og organisationer, der er involveret i denne undersøgelse.

Sponsor

Vanderbilt University

Datoer for undersøgelser

Disse datoer sporer fremskridtene for indsendelser af undersøgelsesrekord og resumeresultater til ClinicalTrials.gov. Studieregistreringer og rapporterede resultater gennemgås af National Library of Medicine (NLM) for at sikre, at de opfylder specifikke kvalitetskontrolstandarder, før de offentliggøres på den offentlige hjemmeside.

Studer store datoer

Studiestart (Faktiske)

1. maj 2010

Primær færdiggørelse (Faktiske)

1. maj 2021

Studieafslutning (Faktiske)

1. maj 2021

Datoer for studieregistrering

Først indsendt

4. maj 2010

Først indsendt, der opfyldte QC-kriterier

5. maj 2010

Først opslået (Skøn)

7. maj 2010

Opdateringer af undersøgelsesjournaler

Sidste opdatering sendt (Faktiske)

5. oktober 2021

Sidste opdatering indsendt, der opfyldte kvalitetskontrolkriterier

27. september 2021

Sidst verificeret

1. september 2021

Mere information

Begreber relateret til denne undersøgelse

Nøgleord

Yderligere relevante MeSH-vilkår

Andre undersøgelses-id-numre

  • 091344

Plan for individuelle deltagerdata (IPD)

Planlægger du at dele individuelle deltagerdata (IPD)?

Ingen

Disse oplysninger blev hentet direkte fra webstedet clinicaltrials.gov uden ændringer. Hvis du har nogen anmodninger om at ændre, fjerne eller opdatere dine undersøgelsesoplysninger, bedes du kontakte register@clinicaltrials.gov. Så snart en ændring er implementeret på clinicaltrials.gov, vil denne også blive opdateret automatisk på vores hjemmeside .

Kliniske forsøg med Forhøjet blodtryk

Kliniske forsøg med BQ123

Søg i lignende forsøg

Sponsorer og samarbejdspartnere

Medicinske tilstande

Narkotikainterventioner

CROs by country

CROs in Bangladesh

Betingelser

Sjældne sygdomme

Narkotikainterventioner

Kosttilskud

Sponsor / samarbejdspartnere

Placeringer

Abonner