Induction of Lipid Droplets in Fibroblasts of the Hamster Lung by a Diet High in Vitamin A

Abstract

To investigate the effect of vitamin A on the occurrence of lipid droplets in alveolar fibroblasts, light and electron microscopic studies were carried out on the lungs of Syrian golden hamsters fed on diets with a low, normal, or high vitamin A content for a period of 17 weeks. The feeding of the high vitamin A diet resulted in a considerable increase in size and number of lipid droplets in alveolar fibroblasts. These droplets also occurred in fibroblasts of the visceral pleura, and in fibroblasts of connective tissue around bronchioli and larger blood vessels. Most of the lipid-laden fibroblasts could be recognized as myofibroblasts. The significance of the droplets for the deposition of interstitial materials or for the synthesis of prostaglandins is discussed.