INTEGRATION IN THE VENTRAL MEDULLA AND COORDINATION OF SYMPATHETIC, PAIN AND AROUSAL FUNCTIONS

Citation
Ej. Vanbockstaele et G. Astonjones, INTEGRATION IN THE VENTRAL MEDULLA AND COORDINATION OF SYMPATHETIC, PAIN AND AROUSAL FUNCTIONS, Clinical and experimental hypertension, 17(1-2), 1995, pp. 153-165
Citations number
55
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Pharmacology & Pharmacy","Cardiac & Cardiovascular System
ISSN journal
1064-1963
Volume
17
Issue
1-2
Year of publication
1995
Pages
153 - 165
Database
ISI
SICI code
1064-1963(1995)17:1-2<153:IITVMA>2.0.ZU;2-J
Abstract
The nucleus paragigantocellularis lateralis (PGi) in the rostral ventr al medulla is implicated in several functions including cardiovascular control, respiration, pain and analgesia. More recent studies implica te this region in alertness and attention as well, by virtue of its pr ominent projections to the nucleus locus coeruleus (LC). To investigat e information that is integrated in the PGi, we Used tract tracing to examine brain and spinal projections to this region. Afferents to PGi were found to be functionally diverse and topographically organized. P rojections to the retrofacial PGi are primarily autonomic in nature. A wider range of inputs were found to target the rostral (juxtafacial) aspect of the PGi, including brain nuclei involved in the processing o f somatosensory and auditory stimuli, as well as autonomic areas. Effe rent projections io the LC were also examined in detail. Neuropharmaco logy experiments revealed that the PGI provides a potent excitatory am ino acid input to the LC and an inhibitory input acting at alpha2 rece ptors on LC neurons. PGi neurons projecting to the LC stained for mark ers of adrenaline, enkephalin, GABA and corticotropin releasing factor . Finally, some PGi neurons collateralize to innervate both the LC and the spinal cord. These results suggest that the LC may function in pa rallel to peripheral autonomic systems Providing a cognitive complemen t to sympathetic function, and that the PGi may integrate a wide range of inputs to facilitate adaptive responses to urgent environmental ev ents.