Dietary monosodium glutamate increases visceral hypersensitivity in a mouse model of visceral pain.
Neurogastroenterol Motil
; 35(9): e14596, 2023 09.
Article
em En
| MEDLINE
| ID: mdl-37248774
ABSTRACT
BACKGROUND:
Monosodium glutamate (MSG) has been identified as a trigger of abdominal pain in irritable bowel syndrome (IBS), but the mechanism is unknown. This study examined whether MSG causes visceral hypersensitivity using a water-avoidance stress (WAS) mouse model of visceral pain.METHODS:
Mice were divided into four groups receiving treatment for 6 days WAS + MSG gavage, WAS + saline gavage, sham-WAS + MSG gavage, and sham-WAS + saline gavage. The acute effects of intraluminal administration of 10 µM MSG on jejunal extrinsic afferent nerve sensitivity to distension (0-60 mmHg) were examined using ex vivo extracellular recordings. MSG was also applied directly to jejunal afferents from untreated mice. Glutamate concentration was measured in serum, and in the serosal compartment of Ussing chambers following apical administration. KEYRESULTS:
Acute intraluminal MSG application increased distension responses of jejunal afferent nerves from mice exposed to WAS + MSG. This effect was mediated by wide dynamic range and high-threshold units at both physiologic and noxious pressures (10-60 mmHg, p < 0.05). No effect of MSG was observed in the other groups, or when applied directly to the jejunal afferent nerves. Serum glutamate was increased in mice exposed to WAS + MSG compared to sham-WAS + saline, and serosal glutamate increased using WAS tissue (p = 0.0433). CONCLUSIONS AND INFERENCES These findings demonstrate that repeated exposure to MSG in mice leads to sensitization of jejunal afferent nerves to acute ex vivo exposure to MSG. This may contribute to visceral hypersensitivity reported in response to MSG in patients with IBS.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Síndrome do Intestino Irritável
/
Dor Visceral
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Neurogastroenterol Motil
Assunto da revista:
GASTROENTEROLOGIA
/
NEUROLOGIA
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Canadá