[Effect of cordycepin on CX43 expression in the corpus cavernosum of type II diabetes induced erectile dysfunction in rats].

OBJECTIVE: To study the effect of cordycepin on the expression of connexin 43 (CX43) in the corpus cavernosum tissue of the ED rats with type II diabetic mellitus (DM). METHODS: Forty male SD rats were fed with high-fat diet and injected intraperitoneally with STZ solution to induce type II DM, and then divided into 4 groups of an equal number: DM model control, low-dose cordycepin (10.0 mg/kg/d), high-dose cordycepin (30.0 mg/kg/d) and sildenafil positive control (5.0 mg/kg/d). Another 10 male SD rats were taken as blank controls and fed with normal diet. After 6 weeks of intervention, the sexual behavior of the rats was observed, the ratio of intra-cavernous pressure to mean arterial pressure (ICP/MAP) measured, and the corpus cavernosal tissue harvested for observation of the morphology and determination of the expression level of CX43 in the corpus cavernosum by immunohistochemistry. RESULTS: Compared with the DM model controls, the rats in the high-dose cordycepin group showed significantly improved latency and frequency of captures (P < 0.01), increased ICP/MAP ratio (P < 0.05), and improved morphology of the corpus cavernosal tissue. The expression of CX43 was found mainly in the smooth muscle cells of the penile corpus cavernosum, and dramatically higher in the high-dose cordycepin group than in the DM model controls (P < 0.01). CONCLUSION: Cordycepin can effectively improve the erectile function of type Ⅱ diabetic rats by up-regulating the expression of CX43 in the penile corpus cavernosum.

Single-walled carbon nanotubes used as stationary phase in GC.

Single-walled carbon nanotubes (SWNTs) have high surface area, high adsorption ability, and nanoscale interactions. In this study, capillary columns including SWNTs, ionic liquid (IL), and IL + SWNTs for GC were prepared. The separation results showed that SWNTs possessed a wide selectivity toward alkanes, alcohols, aromatic compounds, and ketones, and a SWNT capillary column was a very useful GC column for the separation of gas samples. Coating the IL stationary phase on the SWNT capillary column, the SWNTs were able to improve chromatographic characteristic of ionic liquid. Comparing the IL coated on three graphite carbon black capillary columns, which were prepared by dynamic coating, static coating, and chemical bonding the Carbopack C with on SWNTs capillary column, the capacity factors were much higher on the SWNT column. The SEM showed that SWNTs could be bonded to the inner surface of capillary tubing, and most of them were linked end-to-end to form a layer of network structure of skeletons resulting in a high surface area, which increased the interactions between stationary phase and analytes. This is the first single-wall carbon nanotubes bonded to the fused-silica capillary tubing. In the first approach, SWNTs assist ionic liquid with enhanced chromatographic characteristic in GC. This work indicates that SWNTs make it possible to extend the application range on the newly prepared chromatographic stationary phases for GC.