Effects of Toutongning capsule on enkephalin expression in a rat migraine headache model

Toutongning capsule is used for the treatment of migraine headaches, and has yielded therapeutically beneficial effects. However, whether Toutongning capsule exerts its effects via endogenous opioid peptides remains poorly understood. This study investigated the effects of Toutongning capsule on enkephalin expression in the midbrain of rats with nitroglycerin-induced migraine headache at the mRNA and protein levels. Results confirmed that proenkephalin mRNA levels were significantly upregulated following treatment with Toutongning capsule. The numbers methionine-enkephalin and leucine-enkephalin-positive cells were significantly greater in the migraine headache rats following treatment with Toutongning capsule compared with the model group. Taken together, these results show that Toutongning capsule exerts potentially beneficial effects by promoting enkephalin expression in nitroglycerin-induced migraine headache rats.