| Objective: Obesity is caused by energy imbalance in the body,and Ghrelin can affect the body's energy balance.In this study,ordinary SD rats were induced to become obese rats through a high-fat diet.After six weeks of swimming and dieting,the changes in body weight,Lee's index,and abdominal circumference during exercise were observed.We analyzed the expression of Ghrelin in plasma,hypothalamus,and ARC of rats after the end of the experiment.The experiment is to study the long-term swimming exercise combined with dieting and Ghrelin intrinsic link,and reveal the exact relationship between Ghrelin and the energy balance in the body,to provide a reference for the scientific,rational and comprehensive weight loss program.Methods: This study purchased 130 200-220 g clean grade SD rats,and randomize these rats,including normal control group(NC group)and obesity model establishment group(OM group),every eight rats are raised in a cage.The normal control group was fed normal feed,and the obese model group was fed high-fat diet.After successful model establishment,they were divided into obese control group(OC group),dietary restriction group(DR group),exercise immediate group(E1 group),exercise 3h group(E2 group),exercise dieting immediate group(ED1 Group)and exercise diet 3h group(ED2 group).The rats in the exercise group performed swimming for six weeks,six days a week and 90 minutes a day.All groups of rats were fed a high-fat diet.In the second week,the DR and ED groups were fed an average of 80% of the first week's diet,and from the third week to the sixth week,they were fed an average of 70% of the first week's diet.Rats were measured weekly for body weight,body length,and their Lee's index was calculated.Finally,blood was taken from the femoral artery of rats and the hypothalamus was removed.Ghrelin levels in plasma,hypothalamus,and ARC of rats were analyzed using enzyme-linked immunosorbent assay and immunohistochemistry.Results:1.At the eighth week of establishment of obesity model,body weight and Lee's index of the NC group were significantly lower than those of the OC group(P<0.05).Although the abdominal circumference of the OM group was larger than that of the NC group,there was no significant difference.2.After the six-week swimming exercise in rats,body weight,Lee's index,and abdominal circumference in the DR,ED1,and ED2 groups were significantly lower,compared with the OC group,P<0.01,with the ED1 group being the most significant.Body weight and abdominal circumference were compared with NC group P<0.05,and Lee's index is P<0.01 compared with NC group.The body weight and Lee's index of the E1 and E2 groups did not show a decrease during the six-week swimming exercise.3.After six weeks of swimming in rats,compared with OC group,plasma ghrelin levels of DR group,E2 group,ED1 group and ED2 group were higher than those of OC group,and ED1 group was significantly increased,P<0.01.The plasma ghrelin level in E1 group was significantly lower than that in E2 and ED2 groups(P<0.05),which was significantly lower than that in DR group and ED1 group(P<0.01).Compared with OC group,hypothalamic ghrelin level in E1 group was significantly higher than that in OC group(P<0.05).DR group,E2 group,ED1 group,and ED2 group were also higher than OC group,P<0.01.ED1 was significantly higher than that of E2 group(P<0.05),which was significantly higher than that of DR and E1 groups(P<0.01).The ED2 group was significantly higher than the E1 group,P<0.05.Compared with OC group,the positive expression levels of ARC Ghrelin in DR group,E1 group,and ED1 group decreased,while the DR group and E1 group had no significant decrease,but the positive expression color of DR group was lighter and E1 group was smaller.The level of ARC Ghrelin in the ED1 group was significantly lower than that in the OC group,P<0.01.The E1 and DR group was significantly lower than E2 group,P<0.01.The ED1 group was significantly lower than the DR group,E1 group,and E2 group,P<0.01.The ED2 group was significantly lower than the E2 group,P<0.01,higher than the ED1 group,P<0.01.Conclusion:1.For obese rats induced by a high-fat diet,independent long-term swimming exercise can control their body weight,Lee's index,and the increase of abdominal circumference to a lesser extent without limiting diet,but the effect is not significant.In the absence of exercise,an independent diet can significantly reduce their weight,Lee's index,and abdominal circumference.When swimming and dieting were combined for a long time,the body weight,Lee's index,and abdominal circumference of the rats decreased beyond the independent exercise or diet to achieve the best weight loss.2.For obese rats induced by a high-fat diet,plasma Ghrelin levels decreased slightly after an independent long-term swimming exercise,but this was not significant.With the passage of time after exercise,the consumption of the body reached a certain level,plasma ghrelin levels will increase significantly.Independent dieting can increase plasma ghrelin levels to a large extent,but it is still not significant.Prolonged swimming combined with dieting can significantly increase plasma ghrelin levels immediately after exercise.Due to the lack of food to cause appetite stimulation due to olfactory sensation or to make rats adapt to such a dietary state due to weight loss,plasma ghrelin decreased to some extent at 3h after exercise,but it was not significant.So,the increase of plasma ghrelin level in rats is related to the weight loss caused by energy limitation,and the relationship between them is inversely proportional.On the basis of energy limitation,exercise-induced energy consumption will increase plasma ghrelin levels to a greater extent and stimulate rats to ingest food.3.For obese rats induced by a high-fat diet,the combination of dieting alone and prolonged swimming combined with dieting significantly increased hypothalamic ghrelin levels.The combination of the two increased the level of hypothalamic ghrelin more than the independent diet.After 3hours of independent long-term swimming exercise,the level of hypothalamic Ghrelin increased,but it was not significant.Although the combined movements of the two groups decreased after 3hours,there was no significant difference compared with 3hours after independent exercise.The hypothalamic Ghrelin levels and body weight changes between these four groups indicate the sensitivity of Ghrelin to weight-reduced rats immediately after exercise.For ARC Ghrelin,independent dieting and independent exercise can slightly reduce its positive expression,and the combination of the two can be significantly reduced,which is the same as the sensitivity of the hypothalamic ghrelin to the weight-loss rats immediately after exercise.Moreover,there was no increase in the degree of rise of independent swimming at 3h after exercise,and these changes were slightly different from changes in plasma Ghrelin levels.So,Plasma ghrelin levels are more compensatory for weight loss caused by energy restrictions.ARC Ghrelin,on the other hand,positively regulates long-term aerobic exercise combined with weight loss caused by dieting,and its regulation may play a key role in long-term weight loss. |
PDF Full Text Request