Fig. 4.

Bromine enrichment in basement membranes of human kidney. A normal human kidney specimen was processed for NanoSIMS imaging. ¹²C¹⁴N, ³²S, and ³¹P NanoSIMS images were useful for visualizing morphology. ⁷⁹Br, ⁸¹Br, and ⁷⁹Br/¹²C images revealed bromine enrichment in the basement membrane of glomerular capillaries (yellow arrows), the basement membrane of renal tubules (blue arrows), and the basement membrane of Bowman’s capsule (red arrows). There were several areas of intense bromine enrichment in the mesangial matrix of the glomerulus (red arrowheads). We also observed low amounts of bromine enrichment in the ECM outside of Bowman’s capsule (yellow arrowheads). Quantification of the ⁷⁹Br/¹²C ratios in glomerular capillaries is reported in Fig. 5. ⁷⁹Br/¹²C ratios were multiplied by 10,000. (Scale bars: 20 μm.)