The Study About Heat Stress On Hemodynamics Of Animal Model In Chronic Heart Fatlure

Objective:The Observe influence about heat stress on animals of chronic heart failure hemodynamic and their mechanism.Method:The experiment consisted of two parts.The first part:the observe heat stress on animal of chronic heart failure hemodynamic.This part included two experiments:1.observe influence of heat stress on animal of chronic heart failure hemodynamic. 15 New Zealand rabbits coyonary artery ligated leads to chronic heart failure,they were randomly divided into 3 groups :heat stress group,normal temperature group and sham group,examinating hemodynamic variation after eight weeks, and then animals of heat stress group were laid in high temperature room(42?), till rectal temperature of animals is 42 centigrade and they were maintained 15~ 20 minutes,animals of heart failure were diverted to normal temperature environment after heat stress finish and examination hemodynamic variation at 2.4.8.24 hour .2.To observe relationship between plasm heat shock protein 70 and hemodynamic after heat stress on animal of chronic heart failure. 10 Zew Zealand rabbits coronary artery were ligated ,5 rabbits coronary artery were not ligated but chest was operated open.After coronary artery ligated 8 weeks, 10 rabbits were randomly divided into normal temperature group(n=5) and heat stress group(n=5), and examination hemodynamic and plasm heat shock protein(HSP70) concentration.Animals of HS group are exposed thermal enviroment(42癈),they are maintained 15~20 minutes till their rectal temperature is 42 centigrade,animals of HS group are diverted normal temperature environment after HS finish,separately examination hemodynamic and plasm HSP70 concentration at 2,4% 8 , 24 hour .The second part:investigation of mechanism of signal transduction during heat stress protective function.25 New Zealand rabbits coronary artery are ligated, 5 rabbits coronary artery were not ligated ,but chest was operated open.After coronary artery ligated eight weeks ,25 rabbits are randomly divided into 5 groups:normal group(n=5),HS group(n=5), HS and NG-nitro-L.arginine methylester(L-NAME)group(n=5),normal temperature and L-NAMEgroup(n=5), normal temperature and left arginine (L-Arg)group(n=5). Determining hemodynamic and dection plasm of nitric oxide synthsise(NOS) and cyclic guanosine monophosphate (cGMP) concentration.Animals of HS are laid hyperthmia environment(42), they are maintained 15~20 minutes till their rectal temperature is 42 centigrade, animals of HS group are placed normal temperature environment after HS finish,separately examination hemodynamic and plasm NOS and cGMP concentration at 2 4,8, 24 hour .Result:The first part: 1 .Compared with hemodynamic worse in all operation groups and sham group after eight weeks.2.Compared with heart rate,left ventricular end diastolic pressure(LVEDP) decrease significantly in HS group and normal temperature group after heat exposure 24 hour.+dp/dtmax increased significantly.3.Compared with plasm HSP70 concentration of operation group is more higher than sham group after eight weeks.4.HSP70 concentration of HS group is more increaser than normal temperature group and HS ago after heat stress on CHF 24 hr.The second part: 1. Compared with hemodynamic worse in all operation groups and sham group after eight weeks.2.Compared with hemodynamic improvement significantly in HS group and normal temperature group after heat exposure 24 hr;there is not variation about hemodynamic of HS and L-NAME group and normal temperature group after heat stress;Hemodynamic of normal and L-Arg group is improvement than normal temperature group. 3.Plasm NOS and cGMP concentration of CHF animals are higher than sham groupACompared with NOS and cGMP increased significantly in HS CHF group than normal temperature group and HS ago after HS 24 hr,NOS and cGMP concentration of normal and L-Arg group is higher than normal temperature group.Conclusiomthere is protective function about heat stress on animals of CHF,chief show hemodynamic of CHF is improvement ,plasm HSP70 concentration is augument and so on, by analysis w...