Long-term diabetes mellitus (DM) is characterized by widespread alterations
of basal lamina (BL). The purpose of the present work was to verify whethe
r the lung is also a target organ damaged in DM. Electron microscopy was pe
rformed on lung and kidney samples (autopsic material) from 6 diabetics and
6 control subjects studying the thickening of BL of different structures (
alveolar epithelial BL, endothelial capillary BL, both fused BL, BL of the
glomerular capillary endothelium and BL of the renal tubules). The results
were as follows: (1) alveolar epithelial BL(mean +/- SD) = 121 +/- 11 nm in
controls and 176 +/- 27 nm in diabetics (p < 0.01), (2) endothelial capill
ary BL = 164 +/- 14 nm in controls and 223 +/- 27 nm in diabetics (p < 0.00
1), (3) both BL fused = 222 +/- 23 nm in controls and 316 +/- 62 nm in diab
etics (p < 0.01), (4) BL of the glomerular capillary endothelium = 374 +/-
44 nm in controls and 626 +/- 249 in diabetics (p < 0.05) and (5) BL of the
renal tubules = 602 +/- 94 nm in controls and 1,083 +/- 376 nm in diabetic
s (p < 0.05). All parts of the lung are equally affected by DM. The thicken
ing of BL is of the same magnitude in lung and kidney. There is no relation
ship between the thickening of the lung BL and the known duration and type
of DM.