Fig. 2

Kidney after 11-week PbO NP inhalation. A–C Kidney in overview image in HE staining (cortex, outer medulla divided into outer and inner stripe—OSOM, ISOM, inner medulla—IM) in control (A) and PbO NP exposed animals (B, C), arrow shows ureter. Scale bar in panels A-C = 1 mm. D Ureter in detail. E Kidney cortex of control animals with glomerulus (g) and proximal (pt) and distal tubules. F, G Kidney of PbO NPs treated samples exhibits metaplasia (arrow) of glomerular (g) parietal epithelium of Bowman’s capsule (F) or dilatation of proximal tubules (pt, G). H Kidney medulla without pathological alternations after exposure to PbO NPs. I–L Detection of CD68-positive cells (marker of macrophages) in kidney (arrows). Scale bar in panels = 100 µm. M–Q TEM images of kidney after inhalation of PbO NPs. M Renal glomerulus (glo) of characteristic apperance. N) typical podocyte (po) with pedicles, capillary with erythrocytes (er) and filtration barrier (fb) of kidney without pathological alteration. O Proximal tubule (pt) without damage. P Large lipid vacuole (li) present in blood vessel. Q Agglomerate of PbO nanoparticles in the epithelial cell of PT (arrow) next to mitochondria (mi). Scale bars are displayed individually for each picture. R Collagen fibers stained with Green Trichrome (GT) were found predominantly around blood vessels (bv). Scale bar in panels = 100 µm. S Gene expression of receptors CD36, SR-A1, Abca1, Abcg1, SR-B1, and phospholipases C after PbO NP inhalation. The graphs values indicate average ± SD; *p < 0.05 by unpaired t-test