Neonatal exposure to monosodium glutamate induces morphological alterations in suprachiasmatic nucleus of adult rat. Issue 1 (21st January 2016)

• Record Type: Journal Article
• Authors: Rojas‐Castañeda, Julio César; Vigueras‐Villaseñor, Rosa María; Chávez‐Saldaña, Margarita; Rojas, Patricia; Gutiérrez‐Pérez, Oscar; Rojas, Carolina; Arteaga‐Silva, Marcela
• Is Part Of: International journal of experimental pathology. Volume 97:Issue 1(2016:Feb.)
• Page Start: 18
• Page End: 26
• Publication Date: 2016-01-21
• Subjects: glial fibrillary acidic protein -- locomotor activity -- monosodium glutamate -- suprachiasmatic nucleus -- vasoactive intestinal polypeptide -- vasopressin; Pathology, Experimental -- Periodicals; 616.07
• DOI: 10.1111/iep.12157
• Languages: English
• ISSNs: 0959-9673

Abstract

Summary: Neonatal exposure to monosodium glutamate (MSG) induces circadian disorders in several physiological and behavioural processes regulated by the suprachiasmatic nucleus (SCN). The objective of this study was to evaluate the effects of neonatal exposure to MSG on locomotor activity, and on morphology, cellular density and expression of proteins, as evaluated by optical density (OD), of vasopressin (VP)‐, vasoactive intestinal polypeptide (VIP)‐ and glial fibrillary acidic protein (GFAP)‐immunoreactive cells in the SCN. Male Wistar rats were used: the MSG group was subcutaneously treated from 3 to 10 days of age with 3.5 mg/g/day. Locomotor activity was evaluated at 90 days of age using 'open‐field' test, and the brains were processed for immunohistochemical studies. MSG exposure induced a significant decrease in locomotor activity. VP‐ and VIP‐immunoreactive neuronal densities showed a significant decrease, while the somatic OD showed an increase. Major axes and somatic area were significantly increased in VIP neurons. The cellular and optical densities of GFAP‐immunoreactive sections of SCN were significantly increased. These results demonstrated that newborn exposure to MSG induced morphological alterations in SCN cells, an alteration that could be the basis for behavioural disorders observed in the animals.