This preclinical investigation examined whether the traditional acupuncture protocol termed Tiaoshen Tongluo delivered by electroacupuncture (EA) can improve learning and memory after cerebral ischemia–reperfusion injury and whether such effects are associated with regulation of hippocampal microglial polarization via the Nrf2/TREM2 signaling pathway. The study used a middle cerebral artery occlusion/reperfusion (MCAO/R) rat model designed to induce learning–memory impairment.
Male Sprague–Dawley (SD) rats were used. The MCAO/R model was produced using the Koizumi intraluminal filament technique. Initial randomization included a 7 d sham group (n = 10), a 14 d sham group (n = 10) and a pre‑model group. After MCAO/R, rats that met predefined criteria for learning–memory impairment in the Morris water maze were enrolled and randomized into four experimental groups: 7 d model, 7 d EA, 14 d model and 14 d EA, with 10 rats per group.
Rats assigned to the EA groups received the Tiaoshen Tongluo stimulation protocol. Acupoints selected were Baihui (GV20), Yintang (GV24+), and bilateral Taichong (LR3) and Hegu (LI4). Each EA session lasted 10 minutes and was performed once daily. Treatment duration was either 7 consecutive days or 14 consecutive days according to group assignment.
Neurological function was evaluated using the modified neurological severity score (mNSS) before and after the intervention period to quantify sensorimotor and reflex deficits. Cognitive function, focusing on spatial learning and memory, was assessed using the Morris water maze test. Rats were screened after MCAO/R and only those exhibiting learning–memory impairment by the maze criteria were randomized into the post‑stroke model and EA treatment groups.
Tissue‑level and cellular outcomes were evaluated in the hippocampus with standard histopathological methods. Hematoxylin–eosin (HE) staining was used to observe general histopathological changes in brain tissue. Nissl staining was applied to examine neuronal morphology and the presence and integrity of Nissl bodies specifically in the hippocampal CA1 region, a structure highly relevant to spatial memory.
The study planned immunofluorescence double staining to interrogate microglial phenotypes and expression of pathway components implicated in neuroinflammation and neuroprotection. The abstract specifies interest in the Nrf2 (nuclear factor erythroid 2‑related factor 2) and TREM2 (triggering receptor expressed on myeloid cells 2) signaling axis as candidate mediators of EA effects on hippocampal microglial polarization. However, the provided source text in this PubMed entry is truncated before reporting the results of those assays, the precise markers used in the double staining, quantitative outcomes, or statistical analyses.
The PubMed/NCBI source text supplies study objectives, methodology, group allocation, EA parameters, and the set of behavioral, histological and immunostaining assays used. The abstract in the available source is truncated and does not include numerical results, statistical comparisons, or the investigators’ explicit conclusions about efficacy, effect sizes, or safety. Therefore, specific findings regarding whether EA improved mNSS or Morris water maze performance, altered hippocampal histology, or modified microglial polarization and Nrf2/TREM2 signaling cannot be stated from this source alone. For full experimental outcomes and interpretation, the complete article text should be consulted.
This controlled animal study evaluated a defined electroacupuncture regimen (Tiaoshen Tongluo) delivered to acupoints GV20, GV24+, LR3 and LI4 for 7 or 14 days in MCAO/R rats with confirmed learning–memory impairment. Behavioral endpoints (mNSS, Morris water maze), histology (HE, Nissl staining of hippocampal CA1) and immunofluorescence targeting microglial phenotype and the Nrf2/TREM2 pathway were specified as outcome measures. The source document on PubMed provides methods and planned analyses but does not include the results or conclusions in the available abstract; those details were not reported in the provided source text.