Functional status of microvascular vasomotion is impaired in spontaneously hypertensive rat

Figures

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  Figure 1. Functional status of pancreatic islet microvascular vasomotion was impaired in SHRs. (A) Functional status of pancreatic islet microvascular vasomotion in WKYs was assessed based on the dynamic microvascular blood perfusion data. (B) Functional status of pancreatic islet microvascular vasomotion in SHRs. (C) Functional status of pancreatic islet microvascular vasomotion in insulin treated SHRs (SHR-Ts). The dynamic velocity of microvascular blood flow was shown in the rectangular insert. The microvascular blood perfusion between the dashed lines (5 s) was extracted in the square insert. The red line represents microvascular blood perfusion data of WKYs; the blue line represents perfusion data of SHRs; the green line represents perfusion data of SHR-Ts; PU, perfusion unit. (D) Distribution patterns of pancreatic islet microvascular blood perfusion in WKYs, SHRs and SHR-Ts. The distribution pattern was compared using microvascular blood perfusion data derived from laser Doppler monitoring. WKYs and SHR-Ts showed a higher blood perfusion pattern, whereas SHRs displayed a relatively lower scale blood perfusion pattern. Red dots, blood perfusion of WKYs. Blue dots, blood perfusion of…

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  Figure 2. Impaired pancreatic islet function in SHRs was negatively correlated with functional status of pancreatic islet microvascular vasomotion. (A) Intraperitoneal glucose tolerance test. Fasted rats in both groups received an i.p. injection of glucose (2 g/kg body weight). Blood glucose levels were measured at the indicated times (0, 15, 30, 60 and 120 min). SHRs exhibited significantly impaired glucose tolerance following glucose administration compared with its normotensive WKYs. (B) Area under the curve (AUC) was calculated by the trapezoidal method to measure the degree of blood glucose tolerance impairment. SHRs had higher AUCglucose values compared with WKYs. (C) Insulin tolerance test. Non-fasted rats in both groups were i.p. administered insulin (1 IU/kg body weight), and blood glucose levels were measured as above at the indicated times (0, 15, 30 and 60 min). (D) AUCinsulin was calculated by the trapezoidal method mentioned above, and the AUCinsulin of WKYs tended to be lower than that of SHRs, although the difference was not significant. (●) represents blood glucose levels of WKYs and (■) represents blood glucose levels of SHRs. Data are presented as mean ± S.E.M. (n = 6…

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  Figure 3. Glucose toxicity impaired iECs function. (A) MS1 were treated with 5.6 mM glucose (control group), 35 mM glucose (HG group), 35 mM glucose plus 10−8 M insulin (HG + I group), 35 mM glucose plus 0.5 mM L-arginine (HG + R group) and 35 mM glucose plus 100 μM β-mercaptoethanol (HG + βME group) respectively and the expressions of eNOS on MS1 were revealed by immune-labelling. Scale bar = 100 μm. (B) Quantitation of immunohistochemical analysis of eNOS expression. The expression of eNOS was normalized against control MS1, relative eNOS staining of other groups were calculated. (C,D) The expression levels of eNOS and p-eNOSser1177 in different groups were analyzed by Western blotting. And the same protein samples were subjected to low temperature SDS-PAGE to evaluate eNOS dimer and monomer. Representative Western blotting images were cropped from the full-length blots. The full-length Western blots were included in the Supplementary information. *P < 0.05 compared with HG group **P < 0.01 compared with HG group. (E) The densitometric ratio of eNOS monomer and dimer. # P < 0.01 compared with HG group. (F) A schematic diagram of Transwell-based permeability assay. MS1 were seeded at full…

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  Figure 4. Glucose toxicity inhibited angiogenic capacity of iECs. (A) Capillary-like tubular structures of MS1 on Matrigel after treatment with 5.6 mM glucose (control), 35 mM glucose (HG group), 35 mM glucose plus 10−8 M insulin (HG + I group), 35 mM glucose plus 0.5 mM L-arginine (HG + R group) and 35 mM glucose plus 100 μM β-mercaptoethanol (HG + βME group) for 24 h (upper panel). Tubes and nets were automatically selected and marked in blue using Wimasis Image Analysis System (lower panel). Blue, the tubular structure. Red, tubes. White, branching points. (B–H) Quantitative analysis of tube formation capacity among groups. (B,C) The covered area (%) and total loop numbers were significantly decreased in HG group. (D,E) Total nets and relative total tube length (normalized against control group) in HG group were significantly higher than those in other groups. (F) Total branching points of capillary-like tubular structures of MS1 from control, HG, HG + I, HG + R and HG + βME group. (G) Relative mean loop area (normalized against control group) of MS1 in different groups. (H) Relative mean loop perimeter (normalized against control group) of MS1 in different groups. *P < 0.05 compared…

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  Figure 5. Glucose toxicity suppressed the migratory capacity of iECs. (A) MS1 cells were treated with 5.6 mM glucose (control), 35 mM glucose (HG group), 35 mM glucose plus 10−8 M insulin (HG + I group), 35 mM glucose plus 0.5 mM L-arginine (HG + R group) and 35 mM glucose plus 100 μM β-mercaptoethanol (HG + βME group) for 24 h or 48 h after scratching. (B) The migration distance in the wound healing assays were quantified according to the difference value between the covered area and the original wound area. *P < 0.05 compared with HG group, # P < 0.01 compared with HG group. (C) A schematic diagram of the Transwell-based glucotoxicity assay. MS1 were seeded on a polycarbonate membrane in the upper chamber and migrated MS1 were stained by 0.1% crystal violet. (D) MS1 were treated with 5.6 mM glucose (control), 35 mM glucose (HG group), 35 mM glucose plus 10−8 M insulin (HG + I group), 35 mM glucose plus 0.5 mM L-arginine (HG + R group) and 35 mM glucose plus 100 μM β-mercaptoethanol (HG + βME group) for 24 h and migrated MS1 were stained in violet. (E) The numbers of migrated MS1 were calculated in five different fields (200×) and relative migrated MS1 cells were compared with HG group. #…