RESUMEN
OBJECTIVE: To test the effect of Banxia Xiexin Decoction (, BXD) on the contraction and relaxation of gastric smooth muscle (SM) in diabetic gastroparesis (DGP) model rats, and to explore the mechanism of BXD in the prevention and treatment of DGP through experiments of signal pathway both in vivo and in vitro. METHODS: Sixty Sprague-Dawley rats were divided into 6 groups according to a random number table: control group, model group, high-, medium- and low-dose BXD groups (9.2, 4.6 and 1.8 g/(kg·d), respectively), and domperidone group (10 mg/(kg·d)), 10 rats per group. DGP model was established initially by a single intraperitoneal injection of streptozotocin (STZ), and was confirmed by recording gastric emptying, intestinal transport velocity and gastric myoelectric activity of rats after 2 months. Each group was treated with a corresponding drug for 4 weeks. The mRNA and protein expressions of phospholipase C (PLC), inositol triphosphate (IP3), neuronal nitric oxide synthase (nNOS), and cyclic guanosine monophosphate (cGMP) dependent protein kinase G (PKG) were detected by reverse transcription-polymerase chain reaction and Western blot, respectively, while nitric oxide (NO) and cGMP expressions were detected by enzyme-linked immunosorbent assay. Gastric tissues were obtained from rats for primary cell culture preparation. Gastric SM cells were treated with 0.8 µmol/L of STZ or STZ plus 1,000, 500 and 200 µg/mL of BXD or STZ plus 2.5 µmol/mL of domperidone for 24, 48, 72 or 96 h, respectively. The length of gastric SM cells and intracellular Ca2+ concentration ([Ca2+]i) before and after BXD treatment was measured. RESULTS: Compared with the model group, high- and medium-dose BXD and domperidone significantly increased the expressions of PLC, IP3, NO, nNOS, cGMP and PKG in rat's gastric tissue (P<0.01). Gastric SM cells treated with BXD showed a time- and dose-dependent increase in cell viability (P<0.01). The treatment with high- and medium-dose BXD and domperidone inhibited the increase in gastric SM cells length and increased [Ca2+]i compared with the model cells (P<0.01). CONCLUSIONS: Treatment with high- and medium-dose BXD significantly attenuated STZ-induced experimental DGP in rats. The therapeutic effect of BXD on DGP rats might be associated with the PLC-IP3-Ca2+/NO-cGMP-PKG signal pathway.
Asunto(s)
Proteínas Quinasas Dependientes de GMP Cíclico/metabolismo , Medicamentos Herbarios Chinos/farmacología , Gastroparesia/tratamiento farmacológico , Fosfatos de Inositol/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Nucleótidos Cíclicos/metabolismo , Fosfolipasas de Tipo C/metabolismo , Animales , Señalización del Calcio , Diabetes Mellitus Experimental/tratamiento farmacológico , Modelos Animales de Enfermedad , Masculino , Óxido Nítrico/metabolismo , Ratas , Ratas Sprague-Dawley , EstreptozocinaRESUMEN
In this preliminary study a Chinese autosomal dominant microphthalmia family were investigated and the linkage analyses were performed with six previously reported loci (CHX10, MITF, RX, MCOP, NNO1, NNO2) and six microsatellite markers on chromosome 11 as well. The allelic polymorphisms of those microsatellite markers were identified by using polymerase chain reaction, polyacrylamide gel electrophoresis and silver-staining techniques. The LOD scores between microsatellite markers and the disease were obtained by using MLINK software. Our results showed that the linkage between the microphthalmia in this family with the 6 known loci could be excluded, indicating that the defect gene in this microphthalmia family was probably distinct from those of previously reported microphthalmia families.