Direct projections from the cardiovascular nucleus tractus solitarii to pontine preganglionic parasympathetic neurons: A link to cerebrovascular regulation
| Autor: | Khristofor Agassandian, William T. Talman, Valéria Paula Sassoli Fazan, Valentina Adanina |
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| Rok vydání: | 2002 |
| Předmět: |
Male
Baroreceptor Biology Baroreflex Axonal Transport Rats Sprague-Dawley Parasympathetic nervous system Pons Solitary Nucleus medicine Animals Ganglia Autonomic Nucleus ambiguus Lysine musculoskeletal neural and ocular physiology General Neuroscience Ganglia Parasympathetic Anatomy Retrograde tracing Rats Microscopy Electron medicine.anatomical_structure Dorsal motor nucleus nervous system Cerebrovascular Circulation Nucleus Neuroscience hormones hormone substitutes and hormone antagonists circulatory and respiratory physiology |
| Zdroj: | The Journal of Comparative Neurology. 452:242-254 |
| ISSN: | 1096-9861 0021-9967 |
| DOI: | 10.1002/cne.10372 |
| Popis: | Peripheral or central interruption of the baroreflex or the parasympathetic innervation of cerebral vessels leads to similar changes in regulation of cerebral blood flow. Therefore, we sought to test the hypothesis that the cardiovascular nucleus tractus solitarii, the site of termination of arterial baroreceptor nerves, projects to pontine preganglionic neurons whose stimulation elicits cerebral vasodilatation. The current study utilized both light and electron microscopic techniques to analyze anterograde tracing from the cardiovascular nucleus tractus solitarii to preganglionic parasympathetic neurons in the pons. We further used retrograde tracing from that same pontine region to the cardiovascular nucleus tractus solitarii and evaluated the confluence of tracing from the cardiovascular nucleus tractus solitarii to pontine preganglionic neurons labeled retrogradely from the pterygopalatine ganglia. The cardiovascular nucleus tractus solitarii projected to pontine preganglionic parasympathetic neurons, but more rostral and caudal regions of nucleus tractus solitarii did not. In contrast, all three regions of nucleus tractus solitarii projected to the nucleus ambiguus and dorsal motor nucleus of the vagus. Although not projecting to pontine preganglionic parasympathetic neurons, regions lateral, rostral, and caudal to cardiovascular nucleus tractus solitarii sent projections through the pons medial to the preganglionics. The study establishes the presence of a direct monosynaptic pathway from neurons in the cardiovascular nucleus tractus solitarii to pontine preganglionic parasympathetic neurons that project to the pterygopalatine ganglia, the source of nitroxidergic vasodilatory innervation of cerebral blood vessels. It provides evidence that activation of those preganglionic neurons can cause cerebral vasodilatation and increased cerebral blood flow. Finally, it demonstrates differential innervation of medullary and pontine preganglionic parasympathetic neurons by different regions of the nucleus tractus solitarii. |
| Databáze: | OpenAIRE |
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