Catherine N Hall

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Increases in brain blood flow, evoked by neuronal activity, power neural computation and form the basis of BOLD (blood-oxygen-level-dependent) functional imaging. Whether blood flow is controlled solely by arteriole smooth muscle, or also by capillary pericytes, is controversial. We demonstrate that neuronal activity and the neurotransmitter glutamate evoke(More)
Because regional blood flow increases in association with the increased metabolic demand generated by localized increases in neural activity, functional imaging researchers often assume that changes in blood flow are an accurate read-out of changes in underlying neural activity. An understanding of the mechanisms that link changes in neural activity to(More)
Clarity about the nitric oxide (NO) concentrations existing physiologically is essential for developing a quantitative understanding of NO signalling, for performing experiments with NO that emulate reality, and for knowing whether or not NO concentrations become abnormal in disease states. A decade ago, a value of about 1 microM seemed reasonable based on(More)
Neural activity has been suggested to initially trigger ATP production by glycolysis, rather than oxidative phosphorylation, for three reasons: glycolytic enzymes are associated with ion pumps; neurons may increase their energy supply by activating glycolysis in astrocytes to generate lactate; and activity increases glucose uptake more than O₂ uptake. In(More)
Nitric oxide (NO) functions as an intercellular messenger throughout the brain. For this role to be performed efficiently, there must be a mechanism for neutralizing NO, but whether an active biological process exists, or whether NO is lost mainly through diffusion is unclear. To investigate this issue, rat cerebellar slices were exposed to constant levels(More)
Low nanomolar concentrations of nitric oxide activate guanylyl cyclase to produce cGMP, which has diverse physiological effects. Higher concentrations inhibit mitochondrial respiration at cytochrome c oxidase and this has been proposed to be important physiologically, increasing oxygen permeation into tissue (by reducing the oxygen use of cells near blood(More)
The cerebral circulation is highly specialized, both structurally and functionally, and it provides a fine-tuned supply of oxygen and nutrients to active regions of the brain. Our understanding of blood flow regulation by cerebral arterioles has evolved rapidly. Recent work has opened new avenues in microvascular research; for example, it has been(More)
Pericytes, spatially isolated contractile cells on capillaries, have been reported to control cerebral blood flow physiologically, and to limit blood flow after ischaemia by constricting capillaries and then dying. Paradoxically, a recent paper dismisses the idea of pericytes controlling cerebral blood flow, despite confirming earlier data showing a role(More)
Of 5018 patients who had undergone gastric surgery at St James Hospital, Balham, at least 25 years ago, death certificates have been received for 2768, whilst 1746 patients are still alive and are flagged (Office of Populations, Censuses and Surveys (OPCS) will notify us of their death and its cause) and only 504 could not be traced. Mortality from cancers(More)
In order for nitric oxide (NO) to function as a biological messenger it has to be inactivated, but little is known of how this is achieved. In cells from the brain, we have recently shown the existence of a powerful NO sink that 'shapes' NO signals for targeting its receptor, soluble guanylate cyclase, whilst simultaneously preventing NO rising to toxic(More)