Background: Midazolam is widely used as a sedative and anesthetic induction agent. The aim of this study was to systematically examine the inhibitory mechanisms of midazolam in platelet aggregation.
Methods: The inhibitory mechanisms of midazolam in platelet aggregation were explored by means of analysis of the platelet glycoprotein IIb-IIIa complex, phosphoinositide breakdown, intracellular Ca+2 mobilization, measurement of membrane fluidity, thromboxane B2 formation, and protein kinase C activity.
Results: In this study, midazolam dose-dependently (6-26 microm) inhibited platelet aggregation in human platelets stimulated by agonists. Midazolam also dose-dependently inhibited phosphoinositide breakdown and intracellular Ca+2 mobilization in human platelets stimulated by collagen. Midazolam (6-26 mum) significantly inhibited thromboxane A2 formation stimulated by collagen in human platelets. Moreover, midazolam (15 and 26 mum) dose-dependently decreased the fluorescence of platelet membranes tagged with diphenylhexatriene. Rapid phosphorylation of a platelet protein of Mr 47,000 (P47), a marker of protein kinase C activation, was triggered by collagen (2 microg/ml). This phosphorylation was markedly inhibited by midazolam (26 microm).
Conclusions: These results indicate that the antiplatelet activity of midazolam may be involved in the following pathways: the effects of midazolam may initially be caused by induction of conformational changes in platelet membrane, leading to a change in the activity of phospholipase C, and subsequent inhibition of phosphoinositide breakdown and thromboxane A2 formation, thereby leading to inhibition of both intracellular Ca+2 mobilization and phosphorylation of P47 protein.
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http://dx.doi.org/10.1097/00000542-200203000-00022 | DOI Listing |
J Pediatr Hematol Oncol
January 2025
Departments of Laboratory Medicine.
Fetal and neonatal alloimmune thrombocytopenia (FNAIT) results from maternal antibodies targeting fetal platelets during pregnancy, often causing hemorrhagic manifestations detectable antenatally or shortly after birth. We report an atypical form of FNAIT with delayed onset in a healthy, breastfed male infant who developed diffuse petechiae 2 weeks after birth due to severe thrombocytopenia. The mother was shown to be negative for the human platelet antigen-1a (HPA-1a) allele but had anti-HPA-1a IgG antibodies, while the father and newborn were HPA-1a positive, confirming the diagnosis.
View Article and Find Full Text PDFMedicine (Baltimore)
January 2025
Faculty of Chinese Medicine, Macau University of Science and Technology, Taipa, Macau, China.
Rationale: Thrombotic microangiopathies (TMA) caused by malignant hypertension is an acute and critical disease among rare diseases. Although renal biopsy pathology is a golden indicator for diagnosing kidney disease, it cannot distinguish between primary and secondary TMA and requires a comprehensive diagnosis in conjunction with other laboratory tests and medical history.
Patient Concerns: A 33-year-old young man was hospitalized due to unexplained kidney failure.
Medicine (Baltimore)
January 2025
School of Medical Laboratory Sciences, Faculty of Health Sciences, Institute of Health, Jimma University, Jimma, Ethiopia.
Anemia is a worldwide public health problem and is associated with platelet disorders. The relationship between anemia and platelets is complex, with the association being either normal platelet count or thrombocytosis. Platelets are significantly decreased in patients with anemia, and thrombocytopenia has been documented in patients with severe anemia.
View Article and Find Full Text PDFAdv Skin Wound Care
January 2025
At Mayo Clinic, Rochester, Minnesota, United States, Paul T. Gomez, BS, is Summer Research Fellow, Regenerative Sciences Track, Mayo Clinic Graduate School of Biomedical Sciences; Saranya P. Wyles, MD, PhD, is Consultant, Department of Dermatology; and Karen L. Andrews, MD, is Director, Vascular Ulcer and Wound Healing Clinic/Gonda Vascular Center, and Consultant, Department of Physical Medicine and Rehabilitation. At Mayo Clinic, Jacksonville, Florida, Jennifer R. Arthurs is APRN, Center for Regenerative Medicine; and Alison J. Bruce, MB, ChB, is Consultant, Department of Dermatology.
Background: Chronic nonhealing neuropathic foot ulcers affect approximately 15% to 30% of patients with diabetes mellitus and are associated with significant morbidity and mortality. Although current strategies to address these chronic wounds include a multifactorial approach, clinical outcomes remain poor and warrant improvement. Platelet-rich plasma (PRP), derived from autologous or allogeneic blood, is an emerging regenerative product that aims to serve as an adjuvant to standard diabetic foot ulcer (DFU) treatment.
View Article and Find Full Text PDFCells
December 2024
Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy.
Mutations in the genes , , and cause three clinically overlapping thrombocytopenias characterized by a predisposition to hematological neoplasms. The gene, which encodes a protein involved in protein-protein interactions, is downregulated by RUNX1 during megakaryopoiesis. Mutations in 5'UTR of ANKRD26, leading to ANKRD26-RT, disrupt this regulation, resulting in the persistent expression of ANKRD26, which leads to impaired platelet biogenesis and an increased risk of leukemia.
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