Exp Neurobiol.  2016 Jun;25(3):130-138. 10.5607/en.2016.25.3.130.

Cerebral Hemodynamics and Vascular Reactivity in Mild and Severe Ischemic Rodent Middle Cerebral Artery Occlusion Stroke Models

• Sim J
• Jo A
• Kang BM
• Lee S
• Bang OY
• Heo C
• Jhon GJ
• Lee Y
• Suh M

• KMID: 2308638
• DOI: http://doi.org/10.5607/en.2016.25.3.130

Abstract

Ischemia can cause decreased cerebral neurovascular coupling, leading to a failure in the autoregulation of cerebral blood flow. This study aims to investigate the effect of varying degrees of ischemia on cerebral hemodynamic reactivity using in vivo real-time optical imaging. We utilized direct cortical stimulation to elicit hyper-excitable neuronal activation, which leads to induced hemodynamic changes in both the normal and middle cerebral artery occlusion (MCAO) ischemic stroke groups. Hemodynamic measurements from optical imaging accurately predict the severity of occlusion in mild and severe MCAO animals. There is neither an increase in cerebral blood volume nor in vessel reactivity in the ipsilateral hemisphere (I.H) of animals with severe MCAO. The pial artery in the contralateral hemisphere (C.H) of the severe MCAO group reacted more slowly than both hemispheres in the normal and mild MCAO groups. In addition, the arterial reactivity of the I.H in the mild MCAO animals was faster than the normal animals. Furthermore, artery reactivity is tightly correlated with histological and behavioral results in the MCAO ischemic group. Thus, in vivo optical imaging may offer a simple and useful tool to assess the degree of ischemia and to understand how cerebral hemodynamics and vascular reactivity are affected by ischemia.

Keyword

Stroke; MCAO model; Optical intrinsic signal imaging; Hemodynamics; Arterial reactivity

MeSH Terms

Animals
Arteries
Blood Volume
Cerebrovascular Circulation
Hemodynamics*
Homeostasis
Infarction, Middle Cerebral Artery*
Ischemia
Middle Cerebral Artery*
Neurons
Neurovascular Coupling
Optical Imaging
Rodentia*
Stroke