The effects of lead on collagen biosynthesis in neonatal rats

Experimental lead encephalopathy may be accompanied by a breakdown in the blood-brain barrier. Damage to the brain microvasculature is the earliest change observed. Since capillary basement membranes consist, in part, of collagen, the effects of lead on collagen biosynthesis were studied. Suckling rats were exposed to lead via maternal milk by adding 1, 1.5, or 2% lead acetate to the drinking water at birth. At 2, 3, and 4 weeks of age, rats were injected with 14C-proline and killed 12 hours later. Skin samples were assayed for proline and hydroxyproline. Hydroxyproline was decreased in the 0.45 M NaCl-soluble fraction in 1.5 or 2% lead exposed rats at all ages examined (p < 0.01). Hydroxyproline in the insoluble fraction was significantly decreased at 4 weeks (p < 0.005). The hydroxyproline fraction of total radioactivity was decreased in the soluble fraction at 3 and 4 weeks (p < 0.01). The results suggest that lead inhibits collagen biosynthesis in the neonatal rat.