Ablation of TRPV1 Elevates Nocturnal Blood Pressure in Western Diet-fed Mice

Figures

• 

  Fig. (1). Panel (A) shows the long-term telemetric recording of blood pressure in wild-type (WT) and transient receptor potential vanilloid 1 (TRPV1) gene knockout (TRPV1−/−) mice with normal diet (CON) and western diet (WD). Bar graphs show mean arterial pressure (MAP) during daytime (from 6 am to 6 pm) (B) and nighttime (from 6pm to 6 am) (C) in WT and TRPV1−/− mice, with CON or WD fed. Values are mean ± SEM; n=5; *P<0.05 vs. WT-CON; †P<0.05 vs. TRPV1-/--CON; ‡P<0.05 vs. WT-WD.

• 

  Fig. (2). Effect of WD on urinary norepinephrine at daytime (A) and nighttime (B) in WT and TRPV1−/− mice. Values are mean ± SEM; n=6; *P<0.05 vs. WT-CON; †P<0.05 vs. TRPV1-/--CON; ‡P<0.05 vs. WT-WD.

• 

  Fig. (3). Effects of capsaicin, a specific TRPV1 agonist, on ipsilateral afferent renal nerve activity (ARNA) or contralateral renal sympathetic nerve activity (RSNA). (A) Capsaicin (10–6 M) perfused into the left renal pelvis in WT and TRPV1-/- fed with CON and WD. Quantification of ARNA (B) and RSNA (C). Values are mean ± SEM; n=5-8; *P<0.05 vs. WT-CON; †P<0.05 vs. TRPV1-/--CON; ‡P<0.05 vs. WT-WD.

• 

  Fig. (4). Effects of WD on the baroreflex function. Reflex changes in RSNA (A) and heart rate (HR) (B) in response to blood pressure changes induced by IV injection of phenylephrine (PE, 125 μg/mL) or sodium nitroprusside (SNP, 50 μg/mL). Values are mean±SEM; n=5-8; *P<0.05 vs. WT-CON; †P<0.05 vs. TRPV1-/--CON; ‡P<0.05 vs. WT-WD.

• 

  Fig. (5). Effects of WD on the fasting glucose level and glucose tolerance test. (A) Fasting glucose levels and glucose tolerance test were measured in WT and TRPV1–/– mice before and after i.p. glucose (2g/kg body weight). (B) Mean area under the curve (AUC) of glucose was calculated. Values are mean±SEM; n=5; *P<0.05 vs. WT-CON; †P<0.05 vs. TRPV1-/--CON; ‡P<0.05 vs. WT-WD.

• 

  Fig. (6). Effects of WD on the fasting insulin and leptin level. Daytime collected the serum at 2pm, and nighttime collected the serum at 12am. Values are mean±SEM; n=5; *P<0.05 vs. WT-CON; †P<0.05 vs. TRPV1-/--CON; ‡P<0.05 vs. WT-WD.

• 

  Fig. (7). Adipose tissue hematoxylin and eosin (HE) staining. H&E-stained sections are shown from the epididymal adipose tissue of WT or TRPV1-/- mice with CON or WD fed mice. The arrows indicate the infiltration of immune cells in adipose tissue. Scale bar=100μm.

• 

  Fig. (8). Effects of Western diet (WD) on TNF-α (A), IL-6 (B), and leptin (C) from the adipose tissue. TNF-α antagonist III, R-7050 (10–6 M) decrease the leptin (D) released from the adipose tissue. Values are mean±SEM; n=5-8; *P<0.05 vs. WT-CON; †P<0.05 vs. TRPV1-/--CON; ‡P<0.05 vs. WT-WD.