First Author | Jüngling K | Year | 2012 |
Journal | J Physiol | Volume | 590 |
Issue | 16 | Pages | 3701-17 |
PubMed ID | 22570383 | Mgi Jnum | J:200212 |
Mgi Id | MGI:5507794 | Doi | 10.1113/jphysiol.2011.226423 |
Citation | Jungling K, et al. (2012) Activation of neuropeptide S-expressing neurons in the locus coeruleus by corticotropin-releasing factor. J Physiol 590(Pt 16):3701-17 |
abstractText | A recently discovered neurotransmitter system, consisting of neuropeptide S (NPS), NPS receptor, and NPS-expressing neurons in the brain stem, has received considerable interest due to its modulating influence on arousal, anxiety and stress responsiveness. Comparatively little is known about the properties of NPS-expressing neurons. Therefore in the present study, a transgenic mouse line expressing enhanced green fluorescent protein (EGFP) in NPS neurons was used to characterize the cellular and functional properties of NPS-expressing neurons located close to the locus coeruleus. Particular emphasis was on the influence of corticotropin-releasing factor (CRF), given previous evidence of stress-related activation of the NPS system. Upon acute immobilization stress, an increase in c-fos expression was detected immunocytochemically in brain stem NPS-EGFP neurons that also expressed the CRF receptor 1 (CRF1). NPS-EGFP neurons were readily identified in acute slice preparations and responded to CRF application with a membrane depolarization capable of triggering action potentials. CRF-induced responses displayed pharmacological properties indicative of CRF1 that were mediated by both a reduction in membrane potassium conductance and an increase in a non-specific cation conductance different from the hyperpolarization-activated cation conductance Ih, and involved protein kinase A signalling. In conclusion, stress exposure results in activation of brain stem NPS-expressing neurons, involving a CRF1-mediated membrane depolarization via at least two ionic mechanisms. These data provide evidence for a direct interaction between the CRF and the NPS system and thereby extend previous observations of NPS-modulated stress responsiveness towards a mechanistic level. |