First Author | Xie AX | Year | 2017 |
Journal | JCI Insight | Volume | 2 |
Issue | 2 | Pages | e90565 |
PubMed ID | 28138563 | Mgi Jnum | J:258504 |
Mgi Id | MGI:6141354 | Doi | 10.1172/jci.insight.90565 |
Citation | Xie AX, et al. (2017) Ganglionic GFAP (+) glial Gq-GPCR signaling enhances heart functions in vivo. JCI Insight 2(2):e90565 |
abstractText | The sympathetic nervous system (SNS) accelerates heart rate, increases cardiac contractility, and constricts resistance vessels. The activity of SNS efferent nerves is generated by a complex neural network containing neurons and glia. Gq G protein-coupled receptor (Gq-GPCR) signaling in glial fibrillary acidic protein-expressing (GFAP(+)) glia in the central nervous system supports neuronal function and regulates neuronal activity. It is unclear how Gq-GPCR signaling in GFAP(+) glia affects the activity of sympathetic neurons or contributes to SNS-regulated cardiovascular functions. In this study, we investigated whether Gq-GPCR activation in GFAP(+) glia modulates the regulatory effect of the SNS on the heart; transgenic mice expressing Gq-coupled DREADD (designer receptors exclusively activated by designer drugs) (hM3Dq) selectively in GFAP(+) glia were used to address this question in vivo. We found that acute Gq-GPCR activation in peripheral GFAP(+) glia significantly accelerated heart rate and increased left ventricle contraction. Pharmacological experiments suggest that the glial-induced cardiac changes were due to Gq-GPCR activation in satellite glial cells within the sympathetic ganglion; this activation led to increased norepinephrine (NE) release and beta-1 adrenergic receptor activation within the heart. Chronic glial Gq-GPCR activation led to hypotension in female Gfap-hM3Dq mice. This study provides direct evidence that Gq-GPCR activation in peripheral GFAP(+) glia regulates cardiovascular functions in vivo. |