Abstract
Simple SummaryAlthough organization of the catecholaminergic system, in the porcine vagal motor nuclei of the pig, as well as distribution and chemical nature of the parasympathetic preganglionic neurons innervating the prepyloric region of the porcine stomach in the nucleus, have been well established, the question of a possible direct regulatory interaction between both neuronal systems still remains unknown. We discovered morphological foundations for direct regulatory action of the local TH-immunoreactive neurons on vagal preganglionic parasympathetic efferent neurons supplying the prepyloric region of the porcine stomach.The vagus nerve is responsible for efferent innervation and functional control of stomach functions. The efferent fibers originate from neurons located in the dorsal motor nucleus of the vagus (DMX) and undergo functional control of the local neuroregulatory terminals. The aim of the present study was to examine the existence of morphological foundations for direct regulatory action of the local TH-immunoreactive neurons on parasympathetic efferent neurons supplying the prepyloric region of the porcine stomach. Combined injection of neuronal retrograde tracer Fast Blue into the stomach prepyloric region with TH immunostaining was used in order to visualize spatial relationship between DMX-located stomach prepyloric region supplying neuronal stomata and local TH-IR terminals. We confirmed existence of TH-immunoreactive neural terminals closely opposing the stomach prepyloric region innervating neurons at the porcine DMX area. The observed spatial relationship points out the possibility of indirect catecholaminergic control of the stomach function exerted through preganglionic parasympathetic efferent neurons in the pig.
Highlights
It is generally accepted that the dorsal motor vagal nucleus (DMX) and the nucleus ambiguous constitute a source of preganglionic parasympathetic innervation for the upper gastrointestinal tract through many species, including the cat [1], dog [2], rat [3], as well as the domestic pig [4,5]
Fluorogold tracing studies demonstrated the presence of catecholaminergic neurons intermingled between parasympathetic efferent somata in the DMX area, the question of the spatial relationship between porcine parasympathetic efferent neurons and catecholaminergic neurons remains unclear
The remaining majority of the TH-IR neurons did not co-localize with ChAT
Summary
It is generally accepted that the dorsal motor vagal nucleus (DMX) and the nucleus ambiguous constitute a source of preganglionic parasympathetic innervation for the upper gastrointestinal tract through many species, including the cat [1], dog [2], rat [3], as well as the domestic pig [4,5]. Former tracing studies revealed that, in the pig, parasympathetic efferents supplying the stomach prepyloric region originated exclusively from the dorsal motor vagal nucleus [6], while the nucleus ambiguous innervated the esophagus [7]. Others have found catecholaminergic neurons in rat [9], dog [10], sheep [11], human [12], and swine [13] DMX In the latter, fluorogold tracing studies demonstrated the presence of catecholaminergic neurons intermingled between parasympathetic efferent somata in the DMX area, the question of the spatial relationship between porcine parasympathetic efferent neurons and catecholaminergic neurons remains unclear. The problem of the possible presence of morphological foundations for the direct action of catecholaminergic neurons on preganglionic parasympathetic DMX somata supplying the stomach in the pig remains uncertain. Based on the gathered data, it is hypothesized that, in the porcine DMX, there could be a spatial correlation between “gastric”
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
