| Objective Research on the stress response and gastrointestinal hormones change of wound rabbits in the thermal and humid environment for the aims of providing verify of enhancing resistance,establishing evaluation system and grasping the accurate time to intervene in the stress reaction of wound soldiers under the heat environment.Methods The experiment rabbits (n=24 ) were divided into 4 groups. Each group (n=6) exposed to different condition for 120 minutes. Normal control group:dry temperature (Td) (24+1) C,relative humidity (RH) (55+5)%. Wound group:right crural smashing fracture,Td (24+1) C,RH (55+5)%. Heat group:Td (38+1)C,RH (65+5)% . heat & wound group:Td (38+1)C,RH (65+5)%,right crural smashing fracture. The rectal temperature (Tr),mean arterial pressure (MAP),heart rates (HR) and respiration frequency (RF) were recorded by the biological recorder every 10 min consecutively. Phlebotomized samples at 0 30 60 90 120 min during the experiment and the radioimmunological analysis were used to study the changes of glucagons,motilin (MTL),neuropeptide Y (NPY) and neurotensin (NT) in plasma. Pathological changes of the gastric mucous and the pallium were obtained at 120 min during the experiment.Results (1) There was no change of Tr,HR and RF in the normal group during the experiment. In the heat group and heat & wound groups,the Tr rised directly,HR and RF growed faster and faster,and have significant difference with the normal group (P<0.05) . Under the heat condition for about 40 min later,the RF which in every time phase is quite different with the 0 min phase (P<0.05 ) . (2) In the three kinds of test groups,MAP showed a decline tendency,in the humidity group at 120 min the MAP was quite different with which at 0 min (.P<0.05) . In the wound group it dropped obviously,and had quite difference among every time phase (P<0.05) after the rabbit had been wounded for about 90 min later,the same results could be see in the heat & wound group in 60 min later. (3) In the test groups,the content of glucagons was higher than that in the normal group (P<0.05),but had no difference among the three groups (P>0.05) . It was at high levelduring 60-90 min in the wound group,on the top level at 60 min in the humidity group,and showed obvious ascending tendency in the heat & wound group. (4) Compared with the normal group,the content of MTL is higher in the humidity group and heat & wound group (P<0.001) . The content of MTL in the test groups,all showed climbing tendency during the experiment,and had difference at 60,90,120 min with the 0 min (P<0.05),same as it at 30 min in the other two groups. (5) The content of NPY in the humidity group is higher than that in the normal group (P<0.05),and showed the highest level in the heat & wound group among the three test groups. It was at high level at 60-90 min in the wound group,on top level at 90 min in the humidity group,and displayed insistent ascending tendency in the heat & wound group. (6) The content of NT in the test groups is higher than that in the normal control group (P<0.01),and have quite difference between the humidity group and heat & wound group (.P<0.001) . It on high level at 90-120 min in the wound group,it has the same change as the NT in the other two test group. (7) The pathologic changes had been found in all three test groups,showed tissue loosen and edema among the glands,companied with lymphocyte infiltration,congesting and bleeding on the local gastric mucous,so as to the pallium. The most serious pathologic change could be found in the heat & wound group,and the humidity group took the second place.Conclusion (1) The biological responses to heat stress were more serious than that of wound stress. (2) Heat and wound stress can cause increasing secretion of glucagon,MTL,NPY,NT. The changes of these hormones were consistent with the organism response to stress. (3) The stronger the stimulation was,the earlier stress response was. (4) The stronger stimulation was,the more serious pathological change happened. (5) Meteorological condition of...
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