Objectives: Repetitive Transcranial Magnetic Stimulation (rTMS) potential therapeutic uses have been explored in many conditions including stroke. However, its potential effects on cerebral hemodynamics have not been deeply considered. Transcranial Doppler ultrasonography (TCD) is a promising tool in detecting focal changes of cerebral blood flow velocity (CBFV) and cerebrovascular reactivity (CRV) induced by rTMS. We evaluated possible changes in CBFV and CVR in healthy volunteers.
Methods: Low-frequency (1 Hz) and Sham rTMS were applied over the motor cortex (M1) of the left hemisphere of healthy volunteers. CBFV and CVR were evaluated in the ipsilateral middle cerebral artery (MCA). CVR to hypercapnia was derived from the breath-holding index (BHI). Subjects were randomly assigned to real or sham stimulation.
Results: Maximal CBFV of MCA tended to decrease after 1 Hz M1 rTMS. Low-frequency 1Hz M1 rTMS increased BHI (measured in MCA) immediately after rTMS, and the observed effect vanished after 15 min when applied over M1. We did not observe any significant change in Pulsatility Index (PI) and Resistance Index (RI) measures in all conditions. No significant changes of above mentioned parameters were observed in the sham stimulation group.
Conclusions: Low-frequency rTMS induces a significant modulation of CVR in healthy subjects. This effect should be relevant in acute stroke patients with impaired cerebral autoregulation.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.jns.2010.05.011 | DOI Listing |
J Biophotonics
January 2025
Britton Chance Center for Biomedical Photonics-MoE Key Laboratory for Biomedical Photonics, Huazhong University of Science and Technology, Wuhan, China.
Diabetes mellitus (DM), a chronic metabolic disorder that adversely affects the blood-brain barrier (BBB) and microglial function in the central nervous system (CNS), contributing to neuronal damage and neurodegenerative diseases. However, the underlying molecular mechanisms linking diabetes to BBB dysfunction and microglial dysregulation remain poorly understood. Here, we assessed the impacts of diabetes on BBB and microglial reactivity and investigated its mechanisms.
View Article and Find Full Text PDFJ Neuropathol Exp Neurol
January 2025
Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, United States.
In modern war theaters, exposures to blast overpressures are one of the most common causes of brain injury. These pervasive events result in acute and chronic cerebrovascular degenerative processes. Using a rat model of blast-induced mild traumatic brain injury, we identified intramural periarterial hematomas as early primary acute lesions induced by blast exposures.
View Article and Find Full Text PDFJ Ultrasound
January 2025
Clinical Unit of Neurology, Department of Medicine, Surgery and Health Sciences, University Hospital and Health Services of Trieste, ASUGI, University of Trieste, Strada di Fiume, 447, 34149, Trieste, Italy.
Introduction: Post-stroke cognitive impairment (PSCI) and dementia affect short- and long-term outcome after stroke and can persist even after recover from a physical handicap. The process underlying PSCI is not yet fully understood. Transcranial Doppler ultrasound (TCD) is a feasible method to investigate cerebrovascular aging or dementia, through the pulsatility index (PI), the cerebrovascular reactivity (e.
View Article and Find Full Text PDFJ Cereb Blood Flow Metab
January 2025
Neurovascular Research Laboratory, Faculty of Life Sciences and Education, University of South Wales, Pontypridd, UK.
To what extent sildenafil, a selective inhibitor of the type-5 phosphodiesterase modulates systemic redox status and cerebrovascular function during acute exposure to hypoxia remains unknown. To address this, 12 healthy males (aged 24 ± 3 y) participated in a randomized, placebo-controlled crossover study involving exposure to both normoxia and acute (60 min) hypoxia (Fi = 0.14), followed by oral administration of 50 mg sildenafil and placebo (double-blinded).
View Article and Find Full Text PDFNutrients
January 2025
Department of Obstetrics and Gynaecology, Semmelweis University, Üllői Street 78/a, 1082 Budapest, Hungary.
Background/objectives: Both hyperandrogenism (HA) and vitamin D deficiency (VDD) can separately lead to impaired vascular reactivity and ovulatory dysfunction in fertile females. The aim was to examine the early interactions of these states in a rat model of PCOS.
Methods: Four-week-old adolescent female rats were divided into four groups: vitamin D (VD)-supplemented ( = 12); VD-supplemented and testosterone-treated ( = 12); VDD- ( = 11) and VDD-and-testosterone-treated ( = 11).
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!