title: Identification of NO/sGC signalling in the bulbospinal respiratory pathway after C2-C3 hemisection of the spinal cord in rats.
abstract: Guanylyl cyclase (GC) as the effector molecule for nitric oxide (NO) plays a key role in the NO/cGMP signalling cascade. Based on these observations, our study focused on NO/sGC signalization in the bulbospinal respiratory pathway. The distribution of neuronal nitric oxide synthase (nNOS), β1 subunit of soluble guanylyl cyclase (β1sGC) and synaptophysin (SYN) was explored in the upper part of the respiratory pathway after C2-C3 hemisection of the spinal cord in male Wistar rats. Unilateral injection of Fluorogold into the phrenic nucleus (PN) at C4 level and survival of animals for 2 days revealed many Fluorogold fluorescent neurons in the ventral respiratory group (VRG) of the medulla, mostly on the contralateral side. Under physiological conditions we noted nNOS-fluorescent terminals of VRG neurons around β1sGC fluorescent motoneurons in the PN. A strong depletion of nNOS/SYN fluorescent terminals was noted 8 days after hemisection around alpha motoneurons in the PN on the contralateral side. On the side of injury, nNOS/SYN fluorescent puncta were detected around phrenic motoneurons only sporadically. Phrenic alpha motoneurons responded to C2-C3 hemisection by a loss of β1sGC positivity. The results confirm, that β1sGC immunoreactive phrenic motoneurons are innervated by nNOS positive terminals coming from the VRG.
authors.affiliation: Institute of Neurobiology, Slovak Academy of Sciences, Košice, Slovak Republic.
authors.forename: Ludmila
authors.initials: L
authors.lastname: Capková
authors.forename: Alexandra
authors.initials: A
authors.lastname: Dávidová
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Pavel
authors.forename: Andrea
authors.initials: A
authors.lastname: Kucharíková
authors.forename: Jozef
authors.initials: J
authors.lastname: Radoňak
authors.forename: Karolína
authors.initials: K
authors.lastname: Kuchárová
authors.forename: Viera
authors.initials: V
authors.lastname: Cigánková
authors.forename: Martin
authors.initials: M
authors.lastname: Maršala
authors.forename: Nadežda
authors.initials: N
authors.lastname: Lukáčová
mesh_terms: D000818:Animals; D006162:Guanylate Cyclase / Q000032:analysis / Q000378:metabolism*; D008297:Male; D009434:Neural Pathways / Q000201:enzymology / Q000378:metabolism; D009569:Nitric Oxide / Q000032:analysis / Q000378:metabolism*; D010523:Peripheral Nervous System Diseases / Q000201:enzymology / Q000378:metabolism*; D010791:Phrenic Nerve / Q000201:enzymology / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction; D013119:Spinal Cord Injuries / Q000378:metabolism* / Q000503:physiopathology / Q000601:surgery
chemical_list: D009569:Nitric Oxide; D006162:Guanylate Cyclase