SHRSP.Z-Leprfa /IzmDmcr rats (SPZF) were established as a model of metabolic syndrome by crossing stroke-prone spontaneously hypertensive rats (SHRSP) with Zucker Fatty rats. SPZF rats show hypertension, hyperphagia, obesity, dyslipidemia, and insulin resistance. Many reports have suggested that glucagon-like peptide-1 (GLP-1) and dipeptidyl peptidase-4 (DPP-4) affect various organs. In the study, we observed the expression of GLP-1 and DPP-4 in SPZF rats.Design and Method:
Twelve-week-old male SPZF, lean phenotype (Lean), and Zuckerfa/fa (ZF) were used in this study. After blood pressure measurement, 24-hour urine was collected. The blood, fat tissues and kidneys were collected after anesthesia. Blood GLP-1(7-36) amide and DPP-4 were measured. The 24-hour urinary albumin excretion was measured. GLP-1 receptor (GLP-1R), DPP-4, and catalase in the kidneys were detected by Real time-PCR and Western blotting.Results:
SPZF and Lean showed severe hypertension. Blood glucose, triglycerides, insulin, and TBARS in SPZF were significantly higher compared with ZF and Lean. Fat tissues in SPZF were significantly greater than in Lean and ZF. Serum DPP-4 activity in SPZF was significantly higher than in the other rat groups. GLP-1R protein expression in the SPZF kidney was not different compared with the other rat groups. Twenty-four-hour urinary protein and albumin levels in SPZF rats were significantly higher compared with the other rats.Conclusions:
SPZF showed higher serum DPP-4 activity than in ZF and Lean. Elevated serum DPP-4 activity may depend on high insulin and increased fat tissues. Elevated urinary protein and albumin excretion in SPZF was observed. According to previous reports, elevated serum DPP-4 activity is associated with renal injury in SPZF.