RESUMO
To investigate the effects of rennin angiotensin system blockade on the microvessel density in islets of diabetic rats and its relationship with islet function,diabetes model was created by feeding of high-caloric laboratory chow plus intraperitoneal injection of a small dose of streptozotocin (30 mg/kg). After 8 weeks intervention with perindopril (AE,n=10) or valsartan (AR,n=10),the islet function of the animals was evaluated by intravenous insulin release test (IVIRT). The pancreases were immunohistochemically stained to analyze the content of insulin and vascular endothelial growth factor (VEGF) in the islets. The microvessel density (MVD) of islets was detected by counting CD34 positive cells. The hypoxia inducible factor (HIF)-1α mRNA expression in the islets was detected by RT-PCR. Compared with normal control group (NC,n=10),the area under the curve for insulin from 0 to 30 min (AUCI0-30) of diabetes group (DM,n=8) was decreased by 66.3%;the insulin relative concentration (IRC) of βcell was decreased significantly;the relative content of VEGF was increased obviously [(-4.21±0.13) vs (-4.06±0.29)];MVD in islets was decreased by 71.4%;the relative expression of HIF-1α mRNA was increased by 1.19 times (all P＜0.01). Compared with DM group,the AUCI0-30 of AE and AR group was increased by 44.6% and 34.9% respectively;IRC was also increased significantly;the relative content of VEGF was decreased by 21.2% and 21.7% respectively;MVD was increased by 62.5% and 75.0% respectively;the relative expression of HIF-1α was decreased by 27.2% and 29.0% respectively (all P＜0.01 or P＜0.05). There were no significant differences in the said indexes between group AE and AR. It is concluded that the blockade of RAS may ameliorate islets function of diabetic rats by increasing the MVD in islets.
RESUMO
Objective To investigate the relationship between the biological characteristics and the expres-sion of stromlysin (MMP-7) and microvessel density (MVD) in breast cancer tissue and the effect of MMP-7 on MVD of breast cancer. Methods 60 fresh samples were obtained from patients with breast cancer,and then the ex-pression of MMP-7 and vascular endothelial cell CD34 were studied by means of immunohistochemical assay (SP method). The relationship between MMP-7, MVD and age, tumor size, histological type, lymph node metastasis and expression of ER, PR, PCNA, p53 and CerbB2 was studied. The relationship between the biological characteristics and the expression of MMP-7 and MVD in breast cancer were evaluated. Results The positive expression rote of MMP-7 in the d>2 cm group,the group with lymph node metastasis,the group with positive expression of PCNA, p53 and C-erbB-2 (78.1%,74.2%,71.8%,67.6% and 72.2%)were all higher than that in the d≤2 cm group, the group without lymph node metastasis,the group without positive expression of PCNA,p53 and C-erbB-2(32.1%, 41.3%,38.1%,38.5% and 33.3%) (P<0.05). MVD was higher in the positive breast cancer tissue of the group of d>2 cm(34.61±6.97), the group with lymph node metastasis (34.37±7.50), PCNA ( 33.24±8.39), p53 (33.28±8.94), C-erbB-2 (33.55±8.57) than in the negative breast cancer tissue of the d≤2 cm group ( 28.60±9.82), the group without lymph node metastasis (27.48±8.66), PCNA (26.88±7.89), p53 (21.71± 7.59),C-erbB-2(27.42±27.69) (P<0.05). MVD(33.62±7.36)/ high power lens in the MMP-7 positive group was higher than that (27.86±9.45)/high power lens in the MMP-7 of negative group(P<0.05). The posi-tive expression of MMP-7 was correlated with MVD (r=0.380, P<0.05). Conclusion The high expression of MMP-7 and MVD is associated with the development and metastasis of breast cancer. MMP-7 could promote the mi-crovessel development in mammary cancer.