Barbara Levimán; Ingrid Romero & Ignacio Roa

Monosodium glutamate (MSG) is one of the most widely used food additives due to its flavor-enhancing properties. Experimental studies have suggested that chronic exposure to MSG may induce metabolic disturbances and structural alterations in several organs, particularly the liver. The aim of this study was to determine the effects of neonatal MSG administration on liver morphology and hepatocyte stereological parameters in Sprague-Dawley rats. Neonatal rats were distributed into control and experimental groups receiving subcutaneous MSG administration. Animals were maintained under standard laboratory conditions for up to 16 weeks. Liver samples were collected after euthanasia and processed for histological analysis using hematoxylin-eosin staining. Qualitative and quantitative stereological evaluations were performed, including volume density (Vv), surface density (Sv), and numerical density (Na) of hepatocytes. MSG-treated animals exhibited histological alterations characterized by parenchymal disorganization, sinusoidal dilation, inflammatory infiltration, increased adipose tissue deposition, and signs of fibrosis. Furthermore, significant reductions in stereological parameters were observed compared with controls (p<0.05). These findings suggest that neonatal MSG exposure induces persistent hepatic morphological alterations that may contribute to the development of metabolic-associated liver injury.

KEY WORDS: Monosodium glutamate; Liver; Stereology; Liver fibrosis; Hepatocytes.

LEVIMAN, B.; ROMERO, I. & ROA, I. Neonatal monosodium glutamate administration modifies liver histology and stereological parameters in Sprague Dawley rats. Int. J. Morphol., 44(4):1476-1480, 2026.