PMID- 30978351
OWN - NLM
STAT- MEDLINE
DCOM- 20200716
LR  - 20200716
IS  - 1095-8541 (Electronic)
IS  - 0022-5193 (Linking)
VI  - 472
DP  - 2019 Jul 7
TI  - The effects of cerebral curvature on cortical spreading depression.
PG  - 11-26
LID - S0022-5193(19)30147-X [pii]
LID - 10.1016/j.jtbi.2019.04.006 [doi]
AB  - Neuronal activity evokes a localised increase in cerebral blood flow through 
      neurovascular coupling (NVC), a communication system between a group of cells 
      known as a neurovascular unit (NVU). Dysfunctional NVC can lead to pathologies 
      such as cortical spreading depression (CSD), characterised by a slowly 
      propagating wave of neuronal depolarisation and high extracellular potassium 
      (K(+)) levels. CSD is associated with several neurological disorders such as 
      migraine, stroke, and traumatic brain injury. Insight into the spatial dynamics 
      of CSD in humans is mainly deduced from animal experiments on the smooth 
      lissencephalic brain (in particular murine experiments), however the human cortex 
      is gyrencephalic (highly folded) and is considered likely to exhibit different 
      and more complex patterns of CSD. In this study a large scale numerical NVC model 
      of multiple NVUs is coupled to a vascular tree simulating a two-dimensional 
      cerebral tissue slice. This model is extended with a spatial Gaussian curvature 
      mapping that can simulate the highly folded nature of the human cortex. For a 
      flat surface comparable to a lissencephalic cortex the model can simulate 
      propagating waves of high extracellular K(+) travelling radially outwards from a 
      stimulated area at approximately 6.7 mm/min, corresponding well with multiple 
      experimental results. The high K(+) concentration induces a corresponding wave of 
      vasoconstriction (with decreased blood flow) then slight vasodilation, achieved 
      through cellular communication within the NVU. The BOLD response decreases below 
      baseline by approximately 10% followed by an increase of 1%. For a surface with 
      spatially varied curvature comparable to a section of gyrencephalic cortex, areas 
      of positive Gaussian curvature inhibit wave propagation due to decreased 
      extracellular diffusion rate. Whereas areas of negative curvature promote 
      propagation. Consequently extracellular K(+) is observed travelling as wave 
      segments (as opposed to radial waves) through flat or negatively curved "valleys" 
      corresponding to folds (sulci) in the cortex. If the wave size (defined as the 
      activated area of high K(+) concentration) is too small or diffusion rate too low 
      then wave segments can cease propagation. If the diffusion rate is high enough 
      the wave segments can grow from open ends forming loose spiral waves. These 
      results may provide some insight into the differences seen between human and 
      animal experiments.
CI  - Copyright (c) 2019 Elsevier Ltd. All rights reserved.
FAU - Kenny, Allanah
AU  - Kenny A
AD  - Department of Mechanical Engineering, University of Canterbury, New Zealand. 
      Electronic address: allanah.kenny@pg.canterbury.ac.nz.
FAU - Plank, Michael J
AU  - Plank MJ
AD  - School of Mathematics and Statistics and Te Punaha Matatini, University of 
      Canterbury, New Zealand.
FAU - David, Tim
AU  - David T
AD  - Department of Mechanical Engineering, University of Canterbury, New Zealand.
LA  - eng
PT  - Journal Article
DEP - 20190409
PL  - England
TA  - J Theor Biol
JT  - Journal of theoretical biology
JID - 0376342
RN  - RWP5GA015D (Potassium)
SB  - IM
MH  - Cerebral Cortex/*anatomy & histology
MH  - Computer Simulation
MH  - Cortical Spreading Depression/*physiology
MH  - Humans
MH  - Models, Anatomic
MH  - Potassium/metabolism
OTO - NOTNLM
OT  - Cerebral curvature
OT  - Computational biology
OT  - Cortical spreading depression
OT  - Extracellular space
OT  - Parallel computing
EDAT- 2019/04/13 06:00
MHDA- 2020/07/17 06:00
CRDT- 2019/04/13 06:00
PHST- 2019/02/21 00:00 [received]
PHST- 2019/04/05 00:00 [revised]
PHST- 2019/04/08 00:00 [accepted]
PHST- 2019/04/13 06:00 [pubmed]
PHST- 2020/07/17 06:00 [medline]
PHST- 2019/04/13 06:00 [entrez]
AID - S0022-5193(19)30147-X [pii]
AID - 10.1016/j.jtbi.2019.04.006 [doi]
PST - ppublish
SO  - J Theor Biol. 2019 Jul 7;472:11-26. doi: 10.1016/j.jtbi.2019.04.006. Epub 2019 
      Apr 9.