[Abstract Title]. - Society for Neuroscience

Support: NIH Grant NS-051188
NIH Grant EB00790
Title: Characterization of the spatiotemporal responses of surface and penetrating cerebral
arterioles using two-photon microscopy
Authors: *P. TIAN 1 , I. C. TENG 1 , A. M. DALE 2 , A. DEVOR 2,3 ;
1 Neurosciences, 2 Neurosciences and Radiology, UCSD, La Jolla, CA; 3 MGH, Charlestown, MA
Abstract: A complete mechanistic understanding of vascular-based functional imaging signals,
such as those of functional MRI, requires knowledge of the vascular responses on the level of
individual vessels within a large volume. Two-photon laser scanning microscopy (TPLSM) has
been widely employed to image cerebral cortex about 500 microns below pial surface with 1
micron resolution. Hence, we map the three-dimensional stimulus-evoked spatiotemporal
diameter and velocity changes of single vessels in the rat somatosensory cortex in relation to the
map of the underlying neural activity in vivo using TPLSM.
Electrical forepaw stimuli are presented to rats. The center of neuronal activity is mapped using
recordings of evoked surface potentials. Single-vessel vascular diameter and/or velocity changes
are characterized across multiple cortical columns up to a volume of 4 x 4 x 0.5 mm 3. We
measure both surface vessels (including arteries and veins) and penetrating arterioles/venues and
capillaries that lie in layer II/III. The responses (timing, shape, amplitude) are examined as a
function of cortical depths and the distance from the center of neuronal activity.
Our data show that 1) Similar to our previous findings on the surface arteries/arterioles,
penetrating arterioles (100 to 300 microns deep in the cortex) exhibit biphasic behavior in
response to the stimulus. Namely, vasodilatation is followed by vasoconstriction. 2) There are
temporal laminar specificities of the vascular responses. For example, dilation onset is earlier in
penetrating arterioles in comparison with the parent pial arteries. 3) Both surface and penetrating
arterioles show more vasodilatation near the center of the neuronal activity and more
vasoconstriction further away from the center. 4) Veins show either no diameter change or
diameter decrease.
Disclosures: P. Tian, None; I.C. Teng, None; A.M. Dale, None; A. Devor, None.
Poster
286. Imaging the Nervous System
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 286.6/QQ46
Topic: E.09.a. Energy metabolism