Muscarinic Receptors and BK Channels Are Affected by Lipid Raft Disruption of Salivary Gland Cells.
Int J Mol Sci
; 22(9)2021 Apr 30.
Article
em En
| MEDLINE
| ID: mdl-33946369
ABSTRACT
Activity-dependent fluid secretion is the most important physiological function of salivary glands and is regulated via muscarinic receptor signaling. Lipid rafts are important for G-protein coupled receptor (GPCR) signaling and ion channels in plasma membranes. However, it is not well understood whether lipid raft disruption affects all membrane events or only specific functions in muscarinic receptor-mediated water secretion in salivary gland cells. We investigated the effects of lipid raft disruption on the major membrane events of muscarinic transcellular water movement in human salivary gland (HSG) cells. We found that incubation with methyl-ß-cyclodextrin (MßCD), which depletes lipid rafts, inhibited muscarinic receptor-mediated Ca2+ signaling in HSG cells and isolated mouse submandibular acinar cells. However, MßCD did not inhibit a Ca2+ increase induced by thapsigargin, which activates store-operated Ca2+ entry (SOCE). Interestingly, MßCD increased the activity of the large-conductance Ca2+-activated K+ channel (BK channel). Finally, we found that MßCD did not directly affect the translocation of aquaporin-5 (AQP5) into the plasma membrane. Our results suggest that lipid rafts maintain muscarinic Ca2+ signaling at the receptor level without directly affecting the activation of SOCE induced by intracellular Ca2+ pool depletion or the translocation of AQP5 into the plasma membrane.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Glândulas Salivares
/
Receptores Muscarínicos
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Microdomínios da Membrana
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Canais de Potássio Ativados por Cálcio de Condutância Alta
Limite:
Humans
Idioma:
En
Revista:
Int J Mol Sci
Ano de publicação:
2021
Tipo de documento:
Article