Trial reportBritish journal of clinical pharmacology2009
Morphine is an arteriolar vasodilator in man.
Trial report in British journal of clinical pharmacology, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
12 citing papers in PubMed, 31 citations in OpenAlex.
- Comparing the Effects of Low-Dose Ketamine, Fentanyl, and Morphine on Hemorrhagic Tolerance and Analgesia in Humans.Prehospital emergency care · 2023Trial
- Low-dose morphine reduces pain perception and blood pressure, but not muscle sympathetic outflow, responses during the cold pressor test.American journal of physiology. Heart and circulatory physiology · 2022Trial
- Role of Central Inflammatory and Oxidative Pathways in the Morphine Exacerbation of Cardiovascular Effects of Sepsis in Rats.Pharmaceuticals (Basel, Switzerland) · 2025Article
- Metabolic profiles associated with opioid use and opioid use disorder: a narrative review of the literature.Current addiction reports · 2023Article
- The Effects of Pain and Analgesic Medications on Blood Pressure.Current hypertension reports · 2022Review
- Impact of individual and treatment characteristics on wearable sensor-based digital biomarkers of opioid use.NPJ digital medicine · 2022Article
- Clinical Perspectives and Management of Edema in Chronic Venous Disease-What about Ruscus?Medicines (Basel, Switzerland) · 2022Review
- MRGPRX2 and Adverse Drug Reactions.Frontiers in immunology · 2021Review
- Acute hypertensive crisis and severe headache after concurrent use of armodafinil and tranylcypromine: Case report and review of the literature.Journal of the neurological sciences · 2018Review
- Dexmedetomidine: Current Role in Burn ICU.Translational medicine @ UniSa · 2017Article
- The Impact of Opium Consumption on Blood Glucose, Serum Lipids and Blood Pressure, and Related Mechanisms.Frontiers in physiology · 2016Review
- Pharmacology, basic & clinical: contrasts & coherence.British journal of clinical pharmacology · 2009Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 2 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
aimThe mechanisms of action of morphine on the arterial system are not well understood. The aim was to report forearm vascular responses, and their mediation, to intra-arterial morphine in healthy subjects.
methodsThree separate protocols were performed: (i) dose ranging; (ii) acute tolerance; (iii) randomized crossover mechanistic study on forearm blood flow (FBF) responses to intrabrachial infusion of morphine using venous occlusion plethysmography. Morphine was infused either alone (study 1 and 2), or with an antagonist: naloxone, combined histamine-1 and histamine-2 receptor blockade or during a nitric oxide clamp.
resultsMorphine caused an increase in FBF at doses of 30 microg min(-1)[3.25 (0.26) ml min(-1) 100 ml(-1)][mean (SEM)] doubling at 100 microg min(-1) to 5.23 (0.53) ml min(-1) 100 ml(-1). Acute tolerance was not seen to 50 microg min(-1) morphine, with increased FBF [3.96 (0.35) ml min(-1) 100 ml(-1)] (P = 0.003), throughout the 30-min infusion period. Vasodilatation was abolished by pretreatment with antihistamines (P = 0.008) and the nitric oxide clamp (P < 0.001), but not affected by naloxone. The maximum FBF with pretreatment with combined H1/H2 blockade was 3.06 (0.48) and 2.90 (0.17) ml min(-1) 100 ml(-1) after 30 min, whereas with morphine alone it reached 4.3 (0.89) ml min(-1) 100 ml(-1).
conclusionsIntra-arterial infusion of morphine into the forearm circulation causes vasodilatation through local histamine-modulated nitric oxide release. Opioid receptor mechanisms need further exploration.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.