Effect of electrical forepaw stimulation on capillary transit-time heterogeneity (CTH)
| Autor: | Irene Klærke Mikkelsen, Hugo Angleys, Peter Mondrup Rasmussen, Kim Mouridsen, Changsi Cai, Eugenio Gutiérrez-Jiménez, Nina K. Iversen, Sava Sakadzic, Leif Østergaard, Jonghwan Lee, Sune Nørhøj Jespersen, Mads Merrild |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
medicine.medical_specialty Intravital Microscopy Capillary action Coefficient of variation Hemodynamics Hyperemia Transit time Models Biological Mice 03 medical and health sciences 0302 clinical medicine Forepaw stimulation medicine Animals Bolus tracking Foot Chemistry digestive oral and skin physiology Original Articles Electric Stimulation Capillaries Surgery Mice Inbred C57BL 030104 developmental biology Neurology Functional hyperemia Neurology (clinical) Cardiology and Cardiovascular Medicine Perfusion Blood Flow Velocity 030217 neurology & neurosurgery Biomedical engineering |
| Zdroj: | Gutiérrez-Jiménez, E, Cai, C, Mikkelsen, I K, Rasmussen, P M, Angleys, H, Merrild, M, Mouridsen, K, Jespersen, S N, Lee, J, Iversen, N K, Sakadzic, S & Østergaard, L 2016, ' Effect of electrical forepaw stimulation on capillary transit-time heterogeneity (CTH) ', Journal of Cerebral Blood Flow and Metabolism, vol. 36, no. 12, pp. 2072-2086 . https://doi.org/10.1177/0271678X16631560 |
| ISSN: | 1559-7016 0271-678X |
| Popis: | Functional hyperemia reduces oxygen extraction efficacy unless counteracted by a reduction of capillary transit-time heterogeneity of blood. We adapted a bolus tracking approach to capillary transit-time heterogeneity estimation for two-photon microscopy and then quantified changes in plasma mean transit time and capillary transit-time heterogeneity during forepaw stimulation in anesthetized mice (C57BL/6NTac). In addition, we analyzed transit time coefficient of variance = capillary transit-time heterogeneity/mean transit time, which we expect to remain constant in passive, compliant microvascular networks. Electrical forepaw stimulation reduced, both mean transit time (11.3% ± 1.3%) and capillary transit-time heterogeneity (24.1% ± 3.3%), consistent with earlier literature and model predictions. We observed a coefficient of variance reduction (14.3% ± 3.5%) during functional activation, especially for the arteriolar-to-venular passage. Such coefficient of variance reduction during functional activation suggests homogenization of capillary flows beyond that expected as a passive response to increased blood flow by other stimuli. This finding is consistent with an active neurocapillary coupling mechanism, for example via pericyte dilation. Mean transit time and capillary transit-time heterogeneity reductions were consistent with the relative change inferred from capillary hemodynamics (cell velocity and flux). Our findings support the important role of capillary transit-time heterogeneity in flow-metabolism coupling during functional activation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|