INTRODUCTION
Diabetic gastroparesis is a significant health problem in postmenopausal women and is difficult to treat effectively.Vagal nerve dysfunction is present in diabetic gastroparesis［1］.There is now increasing evidence that Ghrelin stimulates motor activity in gastrointestinal tract［2］.The motor effects must be reflected on the principal frequency and amplitude of the stomach electrogastrogram in the gastric antrum.Some studies demonstrated that Ghrelin may affect gastrointestinal motility via specific Ghrelin receptors located on myenteric,vagal and central neurons［2，3］.We have observed the relationship between plasma Ghrelin levels and electrogastrogram in diabetic man,and the results showed that the principal frequency correlated with the plasma Ghrelin levels in all patients whenever 30 min and 120 min after the standard carbohydrate meals,but the relationship in postmenopausal women with type 2 diabetic gastroparesis is not clearly.Therefore,we conducted the observation in the postmenopausal women with diabetic gastroparesis,and explored relationship between the alteration in Ghrelin and the principal frequency of electrogastrogram.
METHODS
Fifteen postmenopausal women with type 2 diabetic gastroparesis（60±7 years,57±10 kg）involved in this study.All patients had been referred with persistent upper gastrointestinal symptoms,and had undergone normal upper gastrointestinal endoscopies three months of enrolment into the study to rule out gastric outlet obstruction or other pathology.Before the observation,8 diabetic patients had underwent oral metformin or single-meal control treatment as well as 7 patients with insulin injecting treatment,and they had not received estrogen therapy.After 10 h overnight fasts,plasma concentrations of Ghrelin,as well as electrogastrogram were measured at baseline and 30,120 min following the ingestion of standard carbohydrate meal,simultaneously.Samples（10 ml）were collected into plastic lithium heparin tubes containing 0.6 mg aprotonin.Samples were immediately centrifuged,and plasma separated and stored at-80 ℃ until assay.We use the immunoassay kit（ELISA Kit.USA ）for this study.Statistical analysis was treated by SPSS11.5.
RESULTS
When we use the 2 independent samples tests to measure the statistic between the baseline Ghrelin levels and the postprandial Ghrelin levels,the results are showed below Tables 1,2.
Table 1 Ranks
Note:Ghr=Ghrelin
Table 2 Test statistics（b）
Note:a Not corrected for ties;b Grouping Variable:group;Ghr=Ghrelin
Figure 1 Relationship between the alteration in Ghrelin and the principal frequency of eletrogastrogram of the patiens:（a）All patients;（b）Metformin group;（c）Insulin group
Linear regressions showed that the varying of Ghrelin levels（baseline Ghrelin levels:30 min Ghrelin levels;baseline Ghrelin levels:120 min Ghrelin levels）is not significant different when comparing the principal frequency of electrogastrogram（baseline value:120 min） Figure 1a,b,c.
CONCLUSIONS
When woman being overweight after menopause results in insulin resistance and worsening in diabetes,baseline Ghrelin are decreased in the postmenopausal women［5］.Some studies demonstrated that metabolic syndrome relates with insulin resistance and obesity in postmenopausal women［4］.The dysregulation of Ghrelin secretion profiles during a euglycemic/hyperinsulinemic clamp is associated with insulin resistance［7］.But our data showed that the baseline Ghrelin levels are significantly fluctuated both in the insulin injection group and the single-meal control and exercise group.Although Ghrelin induces a specific motor pattern in the fasted state and acts postprandially to accelerate gastric emptying［6］,our data showed that the varying of plasma Ghrelin in postmenopausal women with type 2 diabetic gastroparesis did not differ significantly both between the baseline Ghrelin levels vs.the levels30 min after mixed meals;and baseline Ghrelin levels vs. the levels 120 min after mixed meals.Although these data may not reflect alterations of Ghrelin correlated with the principal frequency of electrogastrogram in postmenopausal women with type 2 diabetic gastroparesis,the findings suggest that plasma Ghrelin may be impaired by many risk factors in those patients［8,9,10］.Long-term studies are needed to find those risk factors.