| The cold is one of the most universal stressor in northern animal, which is an important factor to restrict northern livestock farming development leading to the direct and indirect economic loss.Fatty tissue not only is an unique fat storing organ,but also is an extremely important endocrine and paracrine organ, it can produce and secrete the massive adipocytokines including leptin?adiponectin?resistance and so on. They can regulate fatty tissue cell own metabolism, affect the multiplication and the deposition of the fatty cell. Simultaneously, they can enter the blood, form the complex feedback network by endocrine signal together with nerve center, liver, skeletal muscle, blood vessel endothelium, brain and island of pancreas and so on. They can adjust the hypothalamus, the pituitary gland, the adrenal gland axis and sexual gland function, to adjust insulin secretion,maintain glucose and fat metabolism and so on. The cold stress responded the physiological mechanism involves all organizations and the organ nearly, In cold stress organism adjusts material metabolism and the energy metabolism by activing sympathesis-suprarenal medulla system,hypothalamus-pituitary gland-adrenal cortex system,hypothalamus -pituitary gland-glandula thyreoidea axis.When organism under certain cold stress condition, the fatty tissue displays the self-control action fully in order to adapt the environment change, certain blood physiology biochemistry and the endocrine index in fatty tissue can have changed.This experiment apply fluorescence quota PCR technology to observe leptin?adiponectin?resistance mRNA expression change in the neck?the hypodermic?the internal organs mesenterium fatty tissue with different cold stress intensity(0～4℃,-5～0℃,-10～-6℃),to approach relations between the leptin ? adiponectin ? resistance mRNA expression level and the cold stimulation intensity, to provide the theory and the experiment on how cold stress influence fat metabolism, simultaneously, to establish fundament for moderately using the cold stress to improve flesh quality in the animal husbandry production.According to the Sus scrofa leptin,adiponectin,resistin gene sequence, primers and probe were designed,and quantitative research leptin,adiponectin,resistin mRNA in pig fatty tissue after cold stress using real-time fluorescence quantitative PCR.The result showed,with temperature decreasing, Leptin mRNA was significantly decreased (p< 0.01) in neck fat tissue, and there was also a small but statistically significant (p< 0.05) decrease in adiponectin mRNA; resistin mRNA did not change significantly (p>0.05). In hypodermic, internal organs mesenterium fat tissue, the level of leptin and adiponectin mRNA fell in the cold (p< 0.05), but there was no significant change (p>0.05) in resistin mRNA. We conclude that while leptin and adiponectin gene expression is inhibited by exposing to cold, there is no major effect on the expression of resistin genes in fat tissue. Therefore, resistin are unlikely to play a key role in the extensive metabolic adaptations to cold. Leptin and adiponectin mRNA level is reduced by low temperatures in experimental animals, and this effect has been explained as an adaptive mechanism to cold environments.
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