ABSTRACT
ObjectiveTo observe the intervention effect of Ruyi Zhenbao pills （RYZBP） on central pain after thalamic stroke in mice and explore the underlying mechanism. MethodThe central post-stroke pain syndrome （CPSP） model was induced by stereotactic injection of type Ⅳ collagenase into the hypothalamus in mice. The mice were divided into a sham group， a model group， low-， medium-， and high-dose RYZBP groups （0.65， 1.3， 2.6 g·kg-1）， and a pregabalin group （0.075 g·kg-1）. Seven days after modeling， the mice in the groups with drug intervention were administered with corresponding drugs by gavage according to the body mass， once per day for 25 days， while those in the sham group and the model group received an equal volume of normal saline. During this period， mechanical pain and cold pain were detected at different time points， and the apoptotic state of brain tissue cells was detected by in situ terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling （TUNEL）. The 36 classical broad-spectrum inflammatory factors were quantitatively analyzed by liquid-phase chip technology， and differential molecules were screened out and verified by Western blot and enzyme-linked immunosorbent assay （ELISA）. ResultCompared with sham operation group, mechanical pain threshold and cold sensitive pain threshold in model group were significantly changed （P<0.01）. TUNEL results showed that apoptosis of brain cells was obvious. Western blot and ELISA results showed that the expressions of interleukin-1α (IL-1α) and chemokine ligand 5 (CCL5) increased in hypothalamus tissue and serum， while the expressions of Ang-2, granulocyte-colony-stimulating factor (G-CSF) and IL-4 decreased significantly （P<0.01）. Compared with model group， RYZBW dose groups significantly increased mechanical pain threshold， decreased cold sensitivity pain threshold， decreased hypothalamus cell apoptosis ratio （P<0.01）， decreased the expression of IL-1α and CCL5 in hypothalamus tissue and serum， while the expression of ANG-2， G-CSF and IL-4 were significantly increased （P<0.05）. ConclusionRYZBP can relieve hyperalgesia in CPSP mice， and its mechanism is related to the regulation of the expression of pro-/anti-inflammatory factors IL-1α， CCL5， IL-4， G-CSF， and Ang-2.