Objective: Cerebral arterioles in stroke-prone spontaneously hypertensive rats (SHRSP), but not in Sprague-Dawley rats with hypertension induced by nitric oxide (NO) synthase inhibition, undergo inward remodeling. The goal of this study was to determine whether development of vascular inward remodeling may depend on genetic factors.
Design: We examined effects of NO synthase inhibition on the structure of cerebral arterioles in Wistar-Kyoto rats (WKY), a rat strain genetically distinct from Sprague-Dawley.
Methods: Pressure (servonull), diameter (cranial window) and cross-sectional area of the vessel wall (CSA, histologically) were measured in maximally dilated (EDTA) cerebral arterioles in WKY, untreated (n = 8) or treated for 3 months with the NO synthase inhibitor N-nitro-L-arginine methyl ester (L-NAME) (10 mg/kg per day, n = 10) in the drinking water, and in untreated SHRSP (n = 7).
Results: Treatment with L-NAME in WKY increased mean cerebral arteriolar pressure (69 +/- 7 versus 47 +/- 7 mmHg, P < 0.05) and pulse pressure (30 +/- 3 versus 17 +/- 1 mmHg, P < 0.05) to levels significantly lower than in SHRSP (98 +/- 5 and 35 +/- 1 mmHg respectively, P < 0.05). CSA was significantly greater in L-NAME-treated WKY and SHRSP than in untreated WKY (1692 +/- 50 and 1525 +/- 98 microm respectively, versus 1224 +/- 85, P < 0.05). External diameter was significantly less in L-NAME-treated WKY than in untreated WKY (119 +/- 5 versus 135 +/- 4 microm, P < 0.05) but significantly greater than in SHRSP (98 +/- 1 microm, P < 0.05).
Conclusion: Cerebral arterioles undergo hypertrophy and remodeling in WKY with L-NAME-induced hypertension. These findings suggest that genetic factors present in WKY and SHRSP may play a role in the development of vascular inward remodeling during chronic hypertension in rats.
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Antioxidants (Basel)
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Laboratory of Molecular Cardiology, Department of Cardiology 1, University Medical Center of the Johannes Gutenberg-University, 55131 Mainz, Germany.
Noise pollution is a known health risk factor and evidence for cardiovascular diseases associated with traffic noise is growing. At least 20% of the European Union's population lives in noise-polluted areas with exposure levels exceeding the recommended limits of the World Health Organization, which is considered unhealthy by the European Environment Agency. This results in the annual loss of 1.
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January 2025
Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA. Electronic address:
Despite extensive functional mapping studies using rodent functional magnetic resonance imaging (fMRI), interpreting the fMRI signals in relation to their neuronal origins remains challenging due to the hemodynamic nature of the response. Ultra high-resolution rodent fMRI, beyond merely enhancing spatial specificity, has revealed vessel-specific hemodynamic responses, highlighting the distinct contributions of intracortical arterioles and venules to fMRI signals. This 'single-vessel' fMRI approach shifts the paradigm of rodent fMRI, enabling its integration with other neuroimaging modalities to investigate neuro-glio-vascular (NGV) signaling underlying a variety of brain dynamics.
View Article and Find Full Text PDFActa Physiol (Oxf)
February 2025
Deptrtment of Anesthesiology, University of Nebraska Medical Center, Omaha, Nebraska, USA.
Aim: Tissue clearance is a rapidly evolving technology that allows for the three-dimensional imaging of intact biological tissues. Preexisting tissue-clearing techniques, such as Passive Clarity Technique (PACT) and Clear Unobstructed Brain Imaging Cocktails and Computational Analysis (CUBIC), clear tissues adequately but have distinct disadvantages, such as taking extensive time to clear tissues and degradation of endogenous tissue fluorescence. We developed a new tissue-clearing technique combining PACT and CUBIC protocols to map the neural lineages expressing the transient receptor potential vanilloid type 1 (TRPV1) receptor.
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January 2025
Geoffrey Jefferson Brain Research Centre, Manchester Academic Health Science Centre, Northern Care Alliance NHS Foundation Trust, University of Manchester, Manchester, UK.
Objective: Cerebral blood flow (CBF) decline is increasingly recognized as an area of importance for targeting neurodegenerative disorders, yet full understanding of the mechanisms that underlie CBF changes are lacking. Animal models are crucial for expanding our knowledge as methods for studying global CBF and neurovascular coupling in humans are limited and require expensive specialized scanners.
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Int J Mol Sci
December 2024
Dipartimento di Biotecnologie e Scienze della Vita, ASST Sette Laghi, Università degli Studi dell'Insubria, 21100 Varese, Italy.
Hypertension exerts a profound impact on the microcirculation, causing both structural and functional alterations that contribute to systemic and organ-specific vascular damage. The microcirculation, comprising arterioles, capillaries, and venules with diameters smaller than 20 μm, plays a fundamental role in oxygen delivery, nutrient exchange, and maintaining tissue homeostasis. In the context of hypertension, microvascular remodeling and rarefaction result in reduced vessel density and elasticity, increasing vascular resistance and driving end-organ damage.
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