Abstract
Mechanisms coupling blood flow with changes in neuronal activity (functional hyperemia) in the brain, eye, and other organs are not completely understood. Nitric oxide (NO) has been suspected to play an important role, especially in the brain (Iadecola, 1993). We have shown that optic nerve head (ONH) blood flow increases during stimulation of the cat eye by flickering light, depending on the frequency and luminance of the stimulus, using a microscope-mounted infrared laser Doppler system to measure relative changes in ONH blood flow simultaneously with changes in extracellular K+ measured with ion-selective microelectrodes in the vitreous humor immediately above the ONH (Buerk et al., 1995). We have also measured changes in ONH blood flow simultaneously with NO near the ONH using recessed electrochemical microsensors (Buerk et al., 1996). We found that NO increased during neuronal activation by flickering light, and that the functional hyperemia in ONH blood flow and NO increases were significantly attenuated after inhibiting NO synthase. In this report, we describe simultaneous ONH blood flow, NO and PO2 measurements during increased neuronal activity with flickering light. Preliminary results are consistent with coupling of functional hyperemia with increased O2 consumption, but multiple interactions with NO need to be taken into account.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
Similar content being viewed by others
References
Buerk, D.G., Riva, C.E., and S.D. Cranstoun (1995). Frequency and luminance dependent blood flow and K+ ion changes during flicker stimuli in cat optic nerve head. Invest. Ophthalmol. Vis. Sci., 36:2216–2227.
Buerk, D.G., Riva, C.E., and S.D. Cranstoun (1996). Nitric oxide has a vasodilatory role in cat optic nerve head during flicker stimuli. Microvas. Res., 52:13–26.
Cleeter, M.W.J., Cooper, J.M., Darley-Usmar, V.M., Moncada, S., and A.H.V. Schapira (1994). Reversible inhibition of cytochrome c oxidase, the terminal enzyme of the mitochondrial respiratory chain, by nitric oxide: implications for neurogenerative diseases. FEBS Lett., 345:50–54.
Gross, S.S., and M.S. Wolin (1995). Nitric oxide: pathophysiological mechanisms. Annu. Rev. Physiol., 57:737–769.
King, C.E., Melinyshyn, M.J., Mewburn, J.D., Curtis, S.E., Winn, M.J., Cain, S.M., and C.K. Chapler ( 1994). Canine hindlimb blood flow and O2 uptake after inhibition of EDRF/NO synthesis. J. Appl. Physiol., 76:1166–1171.
Kobzik, L., Stringer, B., Balligand, J-L., Reid, M.B., and J.S. Stamler (1995). Endothelial type nitric oxide synthase in skeletal muscle fibers: mitochondrial relationships. Biochem. Biophys. Res. Commun., 211:375–381.
Kosaka, H., and A. Sciyama (1996). Physiological role of nitric oxide as an enhancer of oxygen transfer from erythrocytes to tissues. Biochem. Biophys. Res. Commun., 21:749–752.
Iadecola, C. (1993). Regulation of the cerebral microcirculation during neural activity: Is nitric oxide the missing link? Trends Neurosci., 16:206–214.
Lahiri, S., and D.G. Buerk (in press). Vascular and metabolic effects of nitric oxide synthase inhibition evaluated by tissue PO2 measurements in carotid body. In: Oxygen Transport to Tissue XX, eds: A. Hudetz and D. Bruley, Plenum Press, New York, N.Y.
Petrig, B.L., and C.E. Riva (1991). Near-IR retinal laser Doppler velocimetry and flowmetry: new delivery and detection techniques. Applied Optics, 30:2073–2078.
Pournaras, C.J., Shonat, R.D., Munoz, J-L., and B.L. Petrig (1991). New ocular micromanipulator for measurements of retinal and vitreous physiologic parameters in the mammalian eye. Exp. Eye Res., 53:23–27.
Riva, C.E., Shonat, R.D., Petrig, B.L., Pournaras, C.J., and J.B. Bames (1989). Noninvasive measurement of the optic nerve head circulation. In: Ocular Blood Flow in Glaucoma, eds: G.N. Lambrou, and E.L. Greve, Kugler and Ghedini Publications, Amsterdam, pp. 129–134.
Riva, C.E., Pournaras, C.J., Poitry-Yamate, C.L., and B.L. Petrig. (1990). Rhythmic changes in velocity, volume, and flow of blood in the optic nerve head tissue. Microvas. Res., 40:36–45.
Riva, C.E., Harino, S., Shonat, R.D., and B.L. Petrig (1991). Flicker evoked increase in optic nerve head blood flow in anesthetized cats. Neurosci. Lett., 128:291–296.
Riva, C.E., Harino, S., Petrig, B.L., and R.D. Shonat (1992a). Laser Doppler flowmetry in the optic nerve. Exp. Eye Res., 55:499–506.
Riva, C.E., Harino, S., Petrig, B.L., and R.D. Shonat (1992b). Circulation of the optic nerve head: An investigation with laser Doppler flowmetry. In: Pharmacology of Glaucoma, eds: J.M. Drance, E.M. van Buskirk, and A.H. Neufeld, Williams and Wilkins, Baltimore, MD, pp. 253–264.
Riva, C.E., Cranstoun, S.D., and B.L. Petrig (1996). Effect of decreased ocular perfusion pressure on blood flow and the flicker-induced flow response in the cat optic nerve head. Microvas. Res., 52:258–269, 1996.
Salvemini, D., Misko, T.P., Masferrer, J.L., Scibert, K., Currie, M.G., and P. Needleman (1993). Nitric oxide activates cyclooxygenase enzymes. Proc. Natl. Acad. Sci. USA, 90:7240–7244.
Shen, W., Hintze, T.H., and M.S. Wolin (1995). Nitric oxide. An important signaling mechanism between vascular endothelium and parenchymal cells in the regulation of oxygen consumption. Circ., 92:3505–3512.
Stamler, J.S., Jia, L., Eu, J.P., McMahon, T.J., Demchenko, LT., Bonaventura, J., Gernert, K., and C.A. Piantadosi (1997). Blood flow regulation by S-nitrosohemoglobin in the physiological oxygen gradient. Science, 276:2034–2037.
Xie, Y-W., and M.S. Wolin (1996). Role of nitric oxide and its interaction with Superoxide in the suppression of cardiac muscle mitochondrial respiration. Involvement in response to hypoxia/reoxygenation. Circul., 94:2580–2586.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1998 Springer Science+Business Media New York
About this chapter
Cite this chapter
Buerk, D.G., Atochin, D.N., Riva, C.E. (1998). Simultaneous Tissue PO2, Nitric Oxide, and Laser Doppler Blood Flow Measurements during Neuronal Activation of Optic Nerve. In: Hudetz, A.G., Bruley, D.F. (eds) Oxygen Transport to Tissue XX. Advances in Experimental Medicine and Biology, vol 454. Springer, Boston, MA. https://doi.org/10.1007/978-1-4615-4863-8_19
Download citation
DOI: https://doi.org/10.1007/978-1-4615-4863-8_19
Publisher Name: Springer, Boston, MA
Print ISBN: 978-1-4613-7206-6
Online ISBN: 978-1-4615-4863-8
eBook Packages: Springer Book Archive