Afonso C. Silva, Ph.D.
Cerebral Microcirculation Section
Building 10, Room B1D106
10 Center Drive
Bethesda, MD 20892-1065
Unlike any other organ of the body, the brain is critically dependent on a continuous blood supply. Due to its high energy demands, the brain operates under a tight coupling of neuronal electrical activity to the hemodynamic regulation of energy supply and waste removal. The 'neurovascular coupling' entails a complex, highly redundant array of signaling mechanisms aimed at maintaining homeostasis of the brain parenchyma by regulating CBF on a precise spatial and temporal domain. There is increased evidence that such mechanisms result from an integrated action of neurons, glia and blood vessels, which form a 'neurovascular unit' acting at the cellular level to regulate local CBF. Disruption of these mechanisms causes brain dysfunction and disease.
Our laboratory is interested in understanding the mechanisms of CBF regulation during normal and pathological brain states. The fundamental questions related to cerebral blood flow regulation are:
- What is the smallest vascular unit that adapts independently to brain activity?
- How is this elemental vascular unit related to the cortical architecture?
- What are the major signaling pathways, and the key molecules, that translate a change in brain activity into a vascular response?
To address the above questions, we are working on well-defined rodent and non-human primate models of localized functional brain activation, using modern neuroimaging techniques (fMRI or optical microscopy), in combination with electrophysiology recordings of cortical activity. The cerebrovascular coupling will be tested under the presence of agonists and antagonists of several different known mediators or modulators of CBF. Complimentary information on the cerebrovascular coupling will be studied under pathophysiological brain conditions, such as the ones obtained using experimental animal models of brain stroke. More detailed information about our research can be found in our laboratory's webpage: Cerebral Microcirculation Unit
Yen CC, Papoti D, Silva AC. Investigating the spatiotemporal characteristics of the deoxyhemoglobin-related and deoxyhemoglobin-unrelated functional hemodynamic response across cortical layers in awake marmosets. Neuroimage. 2017.
Silva AC. Anatomical and functional neuroimaging in awake, behaving marmosets. Dev Neurobiol. 2017;77(3):373-389.
Santisakultarm TP, Kersbergen CJ, Bandy DK, Ide DC, Choi SH, Silva AC. Two-photon imaging of cerebral hemodynamics and neural activity in awake and anesthetized marmosets. J Neurosci Methods. 2016;271:55-64.
Park JE, Zhang XF, Choi SH, Okahara J, Sasaki E, Silva AC. Generation of transgenic marmosets expressing genetically encoded calcium indicators. Sci Rep. 2016;6:34931.
Hung CC, Yen CC, Ciuchta JL, Papoti D, Bock NA, Leopold DA, Silva AC. Functional mapping of face-selective regions in the extrastriate visual cortex of the marmoset. J Neurosci. 2015;35(3):1160-72.
Related Scientific Focus Areas
Biomedical Engineering and Biophysics
This page was last updated on November 25th, 2014