ABSTRACT
<p><b>OBJECTIVE</b>To assess the distribution and systemic toxicity of podophyllotoxin-loaded nanostructured lipid carriers (POD-NLC) after topical application on the cervical mucosa in Tibet minipigs.</p><p><b>METHODS</b>Twelve Tibet mini-pigs were randomized into test group and control group to receive topical application of 0.5% POD-NLC and 0.5% POD tincture, respectively, on the cervical mucosa. Cervical mucosal irritation, targeted distribution and systemic absorption of POD were observed at different time points within 24 h after the drug application.</p><p><b>RESULTS</b>No local inflammation reaction was observed in the test group, while serious local irritations (swelling, blisters, blood blisters, erosion and ulceration) occurred in the control group. The fluorescence intensity of POD in the mucosal tissue reached the peak level at 4 h after drug application in the control group, while the POD fluorescence intensity increased slowly and reached the peak level at 16 h in the test group. The peak blood POD concentration occurred at 6 h after POD-NLC application in the test group (14.28∓0.33 ng/mL), as compared to 4 h in the control group (42.46∓0.32 ng/mL). At all the time points within 24 h, blood POD concentration remained significantly lower in the test group than in the control group (P<0.05), and the area under curve of blood POD concentration in the control group was 1.38-fold greater than that in the test group.</p><p><b>CONCLUSION</b>POD-NLC allows sustained release of POD and achieves a higher POD concentration in the mucosal tissue without causing local irritation or obvious systemic toxicity in Tibet minipigs.</p>
ABSTRACT
<p><b>OBJECTIVE</b>To study the dynamic changes of serum CK, CK-MB and myocardium histomorphology in different time periods after single bout and repeated exhausted exercise in rats.</p><p><b>METHODS</b>The animal models of myocardial injury were established by exhausted swimming. Creatine kinase (CK), creatine kinase mass (CK-MB) activities in serum were measured immediately at 3, 6, 12, 24, 48 and 96 hours after exhausted exercise, and the dynamic changes of myocardial histopathology were examined.</p><p><b>RESULTS</b>The CK, CK-MB activities were significantly increased immediately at 3, 6, 12 hours and peaked at 6 hours after single bout of exhausted exercise, meantime the degree of inflammatory cell infiltrate and strong acidophil staining were gradually increased in myocardium of rat, and the myocardial injury was most severe at 12 hours. After 1-week consecutive daily exhausted swimming, CK, CK-MB in serum were obviously increased immediately at, 3, 6, 12, 48 and 96 hours postexercise and peaked immediately and at 96 hours respectively postexercise. There were different degrees of myocardial injury in different time of recovery phase, and was most severe at 48 hours postexercise.</p><p><b>CONCLUSION</b>The myocardial injury was induced by excessive exercise and/or exhausted exercise, and the resulting delayed-onset myocardial injury was further certified.</p>
Subject(s)
Animals , Male , Rats , Creatine Kinase , Blood , Creatine Kinase, MB Form , Blood , Fatigue , Blood , Myocardium , Pathology , Physical Exertion , Physiology , Rats, Wistar , Swimming , PhysiologyABSTRACT
<p><b>OBJECTIVE</b>To study the protective effect of puerarin on stress-induced gastric mucosal injury in rats.</p><p><b>METHOD</b>The model of gastric ulcer was established by restraint plus water-immersion stress in rats. Gastric motility was monitored by the method of "Gas Balloon". Gastric mucosal blood flow was recorded by laser-Doppler flowmetry. Colorimetric method was used to determine the content of NO and ET in gastric mucosal tissue. Meantime the pathologic changes of gastric mucosal was examined.</p><p><b>RESULT</b>Puerarin could significantly attenuated gastric mucosal damage induced by water-immersion stress, inhibited gastric motility, specially decreased the index of gastric motility and percentage of gastric contraction time and numbers of violent contraction. The gastric mucosal blood flow and NO level in gastric mucosal were enhanced, while ET level was reduced by puerarin. The degree of tissue damage in gastric mucosal was also significantly attenuated after administration fo puerarin.</p><p><b>CONCLUSION</b>Puerarin exerts a significant protective effect on water-immersion stress-induced gastric mucosal damage by relaxing the vessels, increasing NO level in gastric mucosal, increasing regional gastric mucosal blood flow and inhibiting gastric motility.</p>