ABSTRACT
OBJECTIVE: To determine the concentrations of evodiamine and rutacarpine in subcutaneous tissues of rats after administration of evodiae extract to evaluate the transdermal drug release properties. METHODS: The rats were treated with abdominal hair removal, followed by covering with black polyethylene film transdermal patch of evodiae extract. The concentrations of evodiamine and rutacarpine in the subcutaneous tissues at different time points were measured by microdialysis sampling technique combined with HPLC method. RESULTS: The maximum concentration(ρmax) of evodiamine in the dialysate was(417.24 ± 43.44) μg · mL-1, time to peak concentration (tmax) was (4.210 ± 0.630) h, and the area under the concentration time curve (AUC0→20) was (3 189.31 ± 789.97) μg · h · mL-1; the ρmax of rutacarpine was(287.13 ± 26.78) μg · mL-1, tmax was (3.980 ± 0.580) h, and the AUC0→16 was(l327.97 ± 245.87) μg · h · mL-1. CONCLUSION: In vivo microdialysis sampling technique combined with HPLC method can be used for the evaluation of transdermal drug release characteristics of evodiamine and rutacarpine. The method has the advantages of simple operation with high sensitivity and specificity. Evodiamine and rutacarpine in evodiae extract have the characteristics of slow transdermal penetration speed but high penetration amount.
ABSTRACT
<p><b>OBJECTIVE</b>To explore the effect of Changji'an Capsule (CA) on mRNA expressions of neuropeptide Y (NPY) in the hypothalamus and colon and serum levels of adreno-cortico-tropic hormone (ACTH) in rats of diarrhea predominant irritable bowel syndrome (IBS-D) model rats.</p><p><b>METHODS</b>Totally 48 SD rats were randomly divided into six groups, i.e., the normal control group, the model group, the Pinaverium Bromide group (PB, 0.018 g/kg), the high dose CA group (2.812 g/kg), the medium dose CA group (1.406 g/kg), and the low dose CA group (0.703 g/kg), 8 in each group. The IBS-D rat model was established by using separation of breast milk + stimulation of acetic acid + constraint of four limbs. Normal saline was given to rats in the normal control group and the model group. All medication lasted for 14 successive days by gastrogavage. The serum content of ACTH was detected by enzyme linked immunosorbent assay (ELISA). The expressions of NPY mRNA in the colon and the hypothalamus were detected using real-time fluorescence quantitative PCR.</p><p><b>RESULTS</b>Compared with the normal control group, the serum ACTH content significantly increased (P < 0.01), the NPY mRNA expression in the colon and the hypothalamus obviously decreased (P < 0.01) in the model control group. Compared with the model group, the serum ACTH obviously decreased in the high dose CA group, the medium dose CA group, and the PB group (P < 0.01, P < 0.05). The NPY mRNA expression in the colon and the hypothalamus were obviously up-regulated in the high dose CA group, the medium dose CA group, the low dose CA group, and the PB group (P < 0.05).</p><p><b>CONCLUSIONS</b>CA could modulate the abnormity of brain-gut axis of IBS-D rats possibly by up-regulating NPY mRNA expressions in the hypothalamus and the colon and down-regulating the ACTH content in the hypothalamic-pituitary-adrenal axis.</p>