Volume 9, Number 2, June 2019
|Number of page(s)||8|
|Published online||24 May 2019|
In vivo microdialysis and in vitro HPLC analysis of the impact of paeoniflorin on the monoamine levels and their metabolites in the rodent brain
Department of Nursing, Jen-Teh Junior College of Medicine, Nursing & Management, Miaoli 356, Taiwan
2 Department of Neurology, China Medical University, Taichung 404, Taiwan
3 Department of Neurology, China Medical University Hospital, Taichung 404, Taiwan
4 Department of Pharmacy, China Medical University Hospital, Taichung 404, Taiwan
5 Department of Food Nutrition and Health Biotechnology, Asia University, Taichung 413, Taiwan
6 Department of Pharmacology, China Medical University, Taichung 404, Taiwan
* Corresponding author. Department of Pharmacology, China Medical University, No. 91, Hsueh-Shih Road, Taichung 404, Taiwan. E-mail address: firstname.lastname@example.org (Y.-F. Chen).
Accepted: 30 April 2019
Background: Paeoniflorin (PF) possesses several effects such as analgesic, the anti-spasmodic effect on smooth muscle. It protects the cardiovascular system and reveals the neuroprotective effect on cerebral ischemia. Monoamine system has been identified to have complex regulatory effects in pain signaling. There are no reports regarding the impact of PF on monoamine levels in the rodent brain by microdialysis. In this study, the effects of PF on monoamines and their metabolites in the rodent brain using in vivo microdialysis and in vitro high performance liquid chromatography (HPLC) analysis.
Methods: Male S.D. rats were anesthetized, fixed onto the stereotaxic instrument to identify the positions of corpus striatum and cerebral cortex. Drilled a hole in the skull of anesthetic rats and proceeded microdialysis, and gave PF (100 μg, i.c.v.). Collected the dialysate and the concentration of monoamines and their metabolites in dialysate and analyzed with HPLC-ECD. Male ICR mice were administered with PF (96 μg, i.c.v.) and with Ringer solution as a control. After 20 mins of administration, the mice were cut off the brain immediately and separated into eight regions according to the method of Glowinski. Added extraction solution to each region, homogenized and extracted for further procedure. The extract was centrifuged, sucked the transparent layer and centrifuged once more. The transparent layer was filtered with a 0.22 μm nylon filter and analyzed with HPLC-ECD (electrochemical detection).
Results: PF increased the content of DOPAC and NE in the cortex, and increased the content of NE and decreased the content of 5-HT in the medulla of the homogenized mice brain tissue. By microdialysis, PF increased the content of DOPAC and 5-HIAA in anesthetic rat cortex and expanded the content of DOPAC, HVA, and 5-HIAA in anesthetic rat striatum.
Conclusions: It reveals that PF could activate the release of monoamines and increase their metabolites in the rodent brain.
Key words: Paeoniflorin / Monoamines and metabolites / Microdialysis / HPLC analysis / Rodent brain
© Author(s) 2019. This article is published with open access by China Medical University
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