Tetramethylpyrazine Prevents Contrast-Induced Nephropathy via Modulating Tubular Cell Mitophagy and Suppressing Mitochondrial Fragmentation, CCL2/CCR2-Mediated Inflammation, and Intestinal Injury

Figure 2

Tubular epithelial cell mitophagy and autophagy were increased in CIN rats and suppressed by TMP pretreatment. Transmission electron microscopy (TEM) images of the kidney in the Con (a), CIN (b–g), CIN+NAC (h), and CIN+TMP (i) rats. The red frame in (b) indicates renal tubular cells undergoing apoptosis in CIN rats as characterized by the condensation of nuclear chromatin. TEM of autophagosomes in CIN rats (orange frames in (c) and (e), indicative of autophagy) and mitochondria encapsulated in autophagosomes in CIN rats (red frames in (c), (e), and (g), indicative of mitophagy) (×9000). (d) Higher magnification TEM of (c) (×27000). (f) Higher magnification TEM of (e) (×27000). Red arrows indicate the normal glomerular basement membrane and podocytes in CON rats (j) and CIN rats (k) (×4200). (l) Quantification of the numbers of autophagic vacuoles in each tubular cell. versus Con and ^## versus CIN.

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