Analgesic effects of Evodia extract cream and its mechanisms in mice / 中国药学杂志

ABSTRACT

OBJECTIVE: To study the analgesic effects of Evodia extract cream and its mechanisms. METHODS: Kunming mice were used as model animals, and hot plate test and formalin test were adopted in analgesia experiments. ELISA test was used to detect the contents of CGRP and PGE2. In addition, the tissue section technique was used to investigate the extent of inflammation cell infiltration in the area of pain. RESULTS: Evodia extract cream with a drug loading ranging from 0.1% to 0.4% could relieve pain induced by noxious heat (P < 0.05), and demonstrated significant analgesic effects in the mice formalin test (P < 0.05) in a dose-dependent manner. RESULTS: from ELISA test showed that Evodia extract cream with a drug loading of 0.2% significantly decreased the expression of CGRP in the pain zone of skin (P < 0.05) 3 min after subcutaneous injection of formalin (0.2% EE), and the expression of CGRP showed significant reduction over time (P < 0.05). But Evodia extract cream with a drug loading ranging from 0.1% to 0.4% had no significant effects on the contents of CGRP and PGE2 in plasma or the content of PGE2 in mice skin. Histological section RESULTS: indicated that the content of inflammation cell infiltration induced by formalin was decreased significantly after topical administration of Evodia extract cream with a drug loading ranging from 0.1% to 0.4% (P < 0.05). CONCLUSION: Topical administration of Evodia extract cream has significant dose-dependent analgesic effects. These findings suggest that the analgesic mechanism of Evodia extract cream is most likely related with exhausting the CGRP and interdicting its conduction and coordinating with anti-inflammatory effect.