Objective: To investigate the purgative activity difference and mechanism of raw and processed Rhei Radix et Rhizoma.
Methods: Mail mice were divided into 9 groups:normal group (saline), model group, Tongbianling group (1 g/kg), raw Rhei Radix et Rhizoma groups (5.00, 2.50 and 1.25 g/kg), processed Rhei Radix et Rhizoma groups (5.00, 2.50 and 1.25 g/kg). After oral administration for 5 days, the diarrhea experiment and intestinal propelling test were carried out to evaluate the purgative effect difference of raw and processed Rhei Radix et Rhizoma. Wistar rats were divided into normal group (normal saline), model group, Tong-bianling group (0.5 g/kg), raw Rhei Radix et Rhizoma group (1.25 g/kg), processed Rhei Radix et Rhizoma group (1.25 g/kg). The changes of levels of gastin( GAS), motilin( MTL), vasoactive peptide (VIP), neurotensin (NT), somatostatin ( SS), acetylcholinesterase (AchE), substance P(SP) and endothelin (ET-1)in blood of the rats and gastin (GAS), motilin( MTL), vasoactive peptide (VIP) and neurotensin (NT) in colon of the rats were detected.
Result: The levels of GAS, MTL, VIP, NT, SS, AchE, SP and ET-1 in serum of raw Rhei Radix et Rhizoma group, and GAS, MTL and VIP in colon of raw Rhei Radix et Rhizoma group were different obviously comparing with the processed one (P < 0.01).
Conclusion: The raw Rhei Radix et Rhizoma and the processed one had obvious differences in regulating intestinal gastrointestinal hormone and neurotransmitter. This effect may be the reason or one of the reasons for purgative activity difference between raw and processed Rhei Radix et Rhizoma.