| Part1Experimental study of severe burn on growth anddevelopment and the level of growth hormone in young miceObjective: To observe the effect of severe burn on body growth,study capacity, exercise capacity and the level of growth hormone inyoung mice.Methods: Young Balb/c mices aged3-4weeks were randomly dividedinto4groups,26mice in each group: control group, negative control group,7-second burn group and10-second burn group. The weight, body lengthand tail length of each mouce were measured before burning. Blood sampleswere obtained at1d,3d and7d after burn. The concentration of the growthhormone in plasma was determined by ELISA. The remaining mice in eachgroup were feed up to adult, and then weight, body length and tail length ofmice were measured. Morris Water Maze Test was used to test the Learningand memory capabilities, then loaded swimming test and pole-climbing testwere used to analyze the exercise capacity.Result:(1)Growth in weight, body length and tail length of the burnedmice (both7s burn group and10s burn group) fell behind (P＜0.05, P＜ 0.01and P＜0.01, respectively).(2)The escape latency of mice in10-second burn group is longer than that of control group(P＜0.05), whilethe frequency of stepping over the platform location is less (P＜0.05). Andthe mice in10-second burn group spend shorter time in the target quadrantthan that of control (P＜0.01).(3)The time of loaded swimming test andpole-climbing test of10-sencond burn group is shorter than that of thecontrol group(P＜0.01, P＜0.05). The time of loaded swimming test of the7-second burn group is also shorter than that of the control group(P＜0.05).(4)The concentrations of growth hormone of the7-sencond burne groupwas lower than that of the control group in the1d and3d after burned (P＜0.05, P＜0.05)；while the level of growth hormone of the10-second burngroup is lower in the1d,3d and7d after burned(P＜0.01, P＜0.01, P＜0.05).Conclusion: The severe burn causes the body growth delay andaffects the Learning and memory capabilities and the exercise capacity. Thepost-burn concentrations of growth hormone in plasma also droppedobviously. Part2The therapeutic effect of rhGH on sevetely burnedyoung miceObjective: To observe the therapeutic effect of rhGH on bodydevelopment, learning and memory capabilities, exercise capacity, the levelof blood albumin, the level of inflammatory factor and so on of theseverely burned young mice.Methods: Young Balb/c mice aged3-4weeks were randomly dividedinto6groups: control group, negative control group,10-second burn group,NS control group, rhGH1mg.kg-1.d-1group and rhGH3mg.kg-1.d-1group. The weight, body length and tail length of mice in each group weremeasured before burning. Blood samples were obtained at1d,3d and5dafter burned from6mice in control group, Negative control group,10-second burn group, and at3d,5d after burn in NS control group, rhGH1mg.kg-1.d-1group and rhGH3mg.kg-1.d-1group. Mice in NS controlgroup, rhGH1mg.kg-1.d-1group and rhGH3mg.kg-1.d-1group weregiven subcutaneous injection of NS, rhGH1mg.kg-1.d-1and rhGH3mg.kg-1.d-1respectively. The concentration of the IL-6and TNF-α wasdetermined by ELISA. The level of albumin，creatinine，glucose andcalcium in plasma were tested simultaneously. The remaining mice in eachgroup were feed up to adult, and then the weight, body length and taillength of mice were measured. Morris Water Maze Test was used to test theLearning and memory capabilities, then loaded swimming test andpole-climbing test were used to analyze the exercise capacity.Result:(1)Growth in weight, body length and tail length of the miceincreased in rhGH3mg.kg-1.d-1group (P＜0.05, P＜0.05and P＜0.01).(2)The escape latency of mice in rhGH group is shorter than that of burngroup, while they spend shorter time in the target quadrant.(3)The time of loaded swimming test and pole-climbing test of rhGH3mg.kg-1.d-1groupis longer than that of burn group(P＜0.05, P＜0.05).(4) After burned, thelevel of serum albumin and calcium decreased, and serum creatinine andblood glucose increased.(5)Two days after treated, serum albumin ofrhGH1mg.kg-1.d-1group and rhGH3mg.kg-1.d-1group increased(P＜0.05, P＜0.05), and serum creatinine of the two group decreased(P＜0.05,P＜0.05), and erum calcium of rhGH3mg.kg-1.d-1group elevated(P＜0.05), and blood glucose reduced(P＜0.05, P＜0.05). Four days aftertreated, serum albumin of rhGH1mg.kg-1.d-1group and rhGH3mg.kg-1.d-1group (P＜0.05, P＜0.05), and serum creatinine of the twogroup decreased(P＜0.05, P＜0.05), and blood glucose reduced(P＜0.05, P＜0.05).(6) The concentrations of TNF-α and IL-6increased significantlyin the1d,3d and5d after burned (P＜0.01, P＜0.01),while theconcentrations of IL-6of two rhGH group decreased in the3d and5d afterburned, while there was no significant alteration in concentrations ofTNF-α (P＜0.05).Conclusion: Via promoting protein synthesis and Inhibiting theinflammatory response, rhGH reduce the high catabolism state after youngmice burned. and improve the body growth delay, learning and memorycapabilities and exercise capacity. |
PDF Full Text Request