The Effect Of NO And NO Donor SNAP On Bacteria's Growth In Vitro

ObjectiveNitric oxide (NO) is a kind of active signaling molecule gases discovered in recently. It is an important medium which can dilatate blood vessel, participate in inflammatory reaction , infective immunoregulation activity and nerve conduction. NO donor is a kind of compound which can release active NO in solution. NO can inhibit inflammatory reaction which induced by bacterial endotoxin. As we known that antibiotics have no effect on inflammatory reaction and tissue damage induced by bacterial endotoxin. If inhalation of NO gases or NO donor combines with antibiotics simultaneously , the patients with severe pneumonia could obtain effective treatment through anti - inflammation and antibiosis. The aim is to investigate the effects of NO and NO doner on bacteria.一, Effect of different concentration NO gases on five bacterial species' growth in vitroMethodsStaphylococcus epidermidis, colibacillus, Staphylococcus aureus, Pseudo-monas aeruginosa, and Candida albicans are the common bacteria leading to respiratory and pulmonary infections in our country. The suspensions of the five species were diluted using normal saline and 10~2 colony forming units (CFU) were plated onto two - group of MH dishes. Each group consisted of 10 dishes . Dilution in one group was 10μl per dish, in the other was 50μl per dish. Cultures exposed to the three different concentrations of NO (10, 25 ,40 PPM) were undertaken in cabinet at 37℃ and 45 -60 percent humidity for 24 hours.Bacterial growth was compared with the same strains incubated in room air under the same condition. CFU were counted and the rate of bacteriostasis was calculated.Results1. Candida albicans of 10μl and 50 ul per dish were significantly inhibited in 10PPM,25PPM,40PPM NO(P<0.05).2. Staphylococcus epidennidis of 10μl per dish were significantly inhibited in 10PPM,25PPM and 40PPM NO(P <0. 05). Staphylococcus epidennidis of 50μl per dish were significantly inhibited in 25PPM,40PPM NO(P <0. 05). But lOPPM NO had no bacteriostatic effect on Staphylococcus epidennidis of 50μl per dish.3. 10 PPM NO had no bacteriostatic effect on colibacillus of 10μl and 50μl per dish ( P > 0.05 ). Colibacillus of 10μl and 50μl per dish were significantly inhibited in 25PPM ,40PPM NO(P < 0.05).4. 10PPM and 25PPM NO had no bacteriostatic effect on Pseudomonas aeruginosa of 10μl and 50μl per dish ( P > 0. 05 ). Pseudomonas aeruginosa of 10μl and 50μl per dish were significantly inhibited in 40PPM NO (P <0.05) .5. Staphylococcus aureus of 10 μl and 50 μl per dish had not been inhibited in lOPPM, 25PPM,40PPM NO(P>0.05).Conclusins1. NO possibly has a selective bacteriostatic effect on some of those bacteri-a. This effect appears to be dose - dependent.2. The sensitivity of the bacteria to NO is different. 二,Effect of SNAP on Bacteria's growth in vitroMethodsThe study was divided into three groups which were SNAP with Sodium L -...