title: Simultaneous measurements of pial arteriolar diameter and laser-Doppler flow during somatosensory stimulation.
abstract: We simultaneously measured pial arteriolar diameter and changes in cortical blood flow during activation of the somatosensory cortex by sciatic nerve stimulation. The pial vasculature was visualized with a closed-cranial window technique in chloralose-anesthetized rats (n = 13). Local blood flow was monitored with laser-Doppler flowmetry. During stimulation of the sciatic nerve (0.2 V, 5 Hz, 20 s), vascular diameter and laser-Doppler flow consistently displayed similar response profiles. With 0.5-ms stimulation pulses, the responses showed an initial peak followed by a smaller but sustained plateau dilation. In contrast, 5-ms pulses evoked a monotonically rising response. Our results support the concept that pial arteriolar diameter changes reflect cortical blood flow responses during somatosensory stimulation.
authors.affiliation: Department of Neurological Surgery, University of Washington School of Medicine, Seattle 98104.
authors.forename: A C
authors.initials: AC
authors.lastname: Ngai
authors.forename: J R
authors.initials: JR
authors.lastname: Meno
authors.forename: H R
authors.initials: HR
authors.lastname: Winn
mesh_terms: D000818:Animals; D001160:Arterioles / Q000033:anatomy & histology* / Q000294:innervation / Q000502:physiology; D001783:Blood Flow Velocity; D004558:Electric Stimulation; D017078:Laser-Doppler Flowmetry; D008297:Male; D010841:Pia Mater / Q000098:blood supply*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000502:physiology; D013003:Somatosensory Cortex / Q000502:physiology*