Induction of Acute Ischemic Stroke in Mice Using the Distal Middle Artery Occlusion Technique

Here, we present a protocol to establish a distal middle cerebral artery occlusion (dMCAO) model through transcranial electrocoagulation in C57BL/6J mice and evaluate the subsequent neurological behavior and histopathological features.

Ischemic stroke remains the predominant cause of mortality and functional impairment among the adult populations globally. Only a minority of ischemic stroke patients are eligible to receive intravascular thrombolysis or mechanical thrombectomy therapy within the optimal time window. Among those stroke survivors, around two-thirds suffer neurological dysfunctions over an extended period. Establishing a stable and repeatable experimental ischemic stroke model is extremely significant for further investigating the pathophysiological mechanisms and developing effective therapeutic strategies for ischemic stroke. The middle cerebral artery (MCA) represents the predominant location of ischemic stroke in humans, with the MCA occlusion serving as the frequently employed model of focal cerebral ischemia. In this protocol, we describe the methodology of establishing the distal MCA occlusion (dMCAO) model through transcranial electrocoagulation in C57BL/6 mice. Since the occlusion site is located at the cortical branch of MCA, this model generates a moderate infarcted lesion restricted to the cortex. Neurological behavioral and histopathological characterization have demonstrated visible motor dysfunction, neuron degeneration, and pronounced activation of microglia and astrocytes in this model. Thus, this dMCAO mouse model provides a valuable tool for investigating the ischemiastroke and worth of popularization.

Stroke is a common acute cerebrovascular disease characterized by high incidences of disability and fatality¹. Of all stroke cases, nearly 80% belong to ischemic stroke². Up to now, intravenous thrombolysis remains one of a limited number of productive approaches for the treatment of acute ischemic stroke. However, the effectiveness of thrombolytic treatment is restricted by the narrow effective time window and the occurrence of hemorrhagic transformation³. In the long-term rehabilitation phase following an ischemic stroke, a considerable number of patients are likely to experience durable neurolo....

The experimental protocol was approved by the Institutional Animal Care and Use Committee of Jianghan University and was conducted in accordance with Experimental Animals Ethical Guidelines issued by the Center for Disease Control of China. Adult male C57BL/6J mice, 10 weeks old, weighted 24-26 g, were used in this protocol. All mice were housed under a 12-h light/dark cycle controlled environment with food and water ad libitum.

1. Preoperative preparation

The key instruments used to perform the dMCAO are the microsurgical instruments set, the isoflurane vaporizer, and the monopolar microsurgical electrocoagulation generator shown in Figure 1. The experimental procedure of this study is illustrated in Figure 2. In brief, a small bone window craniotomy was employed to expose the distal MCA, which was subsequently coagulated to induce permanent focal cerebral ischemia in C57BL/6 mice. Furthermore, the ischemic .......

In the present protocol of the craniotomy electrocoagulation dMCAO model, the surgical procedures are conducted with minimal invasiveness, wherein only a portion of the temporalis muscle is separated to mitigate the adverse effects on masticatory function. The mice all recovered well after the procedure, with no observed instances of feeding difficulties. The MCA can be easily discerned in the temporal bone of the mouse, thereby facilitating precise identification of suitable craniotomy locations. This dMCAO model-induce.......

This study was supported by the Grants from the Nature Science Foundation of Hubei Province (2022CFC057).