ABSTRACT
Objective To evaluate the relationship between melatonin and development of post-herpetic neuralgia (PHN) in rats.Methods Sixty adult Wistar rats of both sexes,aged 3 months,weighing 180-230 g,were randomly divided into A-F 6 groups (n =10 each) using a random number table.Group A served as sham operation group,and inactivated herpes simplex virus type-1 (HSV-1) was inoculated.Group B served as sham operation group,and HSV-1 was inoculated.In group C,pinealectomy was performed and inactivated HSV-1 was inoculated.In group D,pinealectomy was performed,and HSV-1 was inoculated.In group E,pinealectomy was performed,inactivated HSV-1 was inoculated,and melatonin was injected intraperitoneally everyday.In group F,pinealectomy was performed,HSV-1 was inoculated,and melatonin was injected intraperitoneally everyday.HSV-1 or inactivated HSV-1 was inoculated on the left hind paw of the rats at 1 h after pinealectomy,and the dosage of melatonin was 120 mg/kg once a day.The mechanical pain response score (MPRS) was determined before inoculation and on days 1,5,10,20 and 30 post-inoculation.The development of PHN was recorded on day 30 post-inoculation.Results MPRS was significantly higher in group B than in group A,and in group D than in group B (P ＜ 0.05).MPRS was significantly lower in group F than in group D (P ＜ 0.05).PHN was not found in A,C and E groups,and the incidence of PHN was 40％,90％ and 40％,respectively.Compared with group B,the incidence of PHN was significantly increased in group D (P ＜ 0.05),and no significant change was found in group F (P ＞ 0.05).Conclusion Reduction of melatonin secretion is related to the development of PHN in rats.
ABSTRACT
Objective To investigate the effects of Ginkgo biloba extract (Egb) on the levels of matrix metalloproteinase2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) in canine lung tissues during cardiopulmonary bypass (CPB) .Methods Fourteen health canines weighing 14-20 kg were randomly divided into 2 groups (n = 7 each): control group and Egb group. EGb 8 mg/kg in 100 ml normal saline was infused via central vein before opening the thoracic cavity in Egb group, while equal volume of normal saline was used instead of Egb in control group. Blood samples were taken from internal jugular vein at 120 min after aortic unclamping,broncho-alveolar larage fluid was collected and lung permeability index was calculated. Then the animals were killed and the lungs removed for determination of W/D lung weight ratio and contents of MMP-2 and MMP-9.Results Egb significantly decreased lung permeability index, W/D lung weight ratio and contents of MMP-2 and MMP-9 (P ＜ 0.05 or 0.01). Conclusion Egb can attenuate CPB-induced lung injury though decreasing the activities of MMP-2 and MMP-9 in canine lung tissues.