Brain afferents to the medullary dorsal reticular nucleus: a retrograde and anterograde tracing study in the rat

• Type: Article in International Scientific Journal
• Date: 2002

Authors

Almeida, A (Author) Other; Cobos, A (Author) Other; Isaura Tavares (Author) FMUP; Deolinda Lima (Author) FMUP

Journal

Title: European Journal of Neuroscience

Vol. 16

Pages: 81-95

ISSN: 0953-816X

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 39 Citations

Scopus - 45 Citations

Other information

Authenticus ID: P-000-NTB

DOI: 10.1046/j.1460-9568.2002.02058.x

Abstract (EN): The medullary dorsal reticular nucleus (DRt) was recently shown to belong to the supraspinal pain control system; neurons within this nucleus give origin to a descending projection that increases spinal nociceptive transmission and facilitates pain perception [Almeida et al. (1999), Eur. J. Neurosci., 11, 110-122]. In the present study, the areas of the brain that may modulate the activity of DRt neurons were investigated by using of tract-tracing techniques. Injection of a retrograde tracer into the DRt resulted in labelling in multiple areas of the brain. In the contralateral orbital, prelimbic, infralimbic, insular, motor and somatosensory cortices labelling was prominent, but a smaller ipsilateral projection from these same areas was also detected. Strong labelling was also noted in the central amygdaloid nucleus, bed nucleus of stria terminalis and substantia innominata. Labelled diencephalic areas were mainly confined to the hypothalamus, namely its lateral and posterior areas as well as the paraventricular nucleus. In the mesencephalon, the periaqueductal grey, red nucleus and deep mesencephalic nucleus were strongly labelled, whereas, in the brainstem, the parabrachial nuclei, rostroventromedial medulla, nucleus tractus solitarius, spinal trigeminal nucleus, and the parvocellular, dorsal, lateral and ventral reticular nuclei were the most densely labelled regions. All deep cerebellar nuclei were labelled bilaterally. These data suggest that the DRt integrates information from the somatosensory, antinociceptive, autonomic, limbic, pyramidal and extrapyramidal systems while triggering its descending facilitating action upon the spinal nociceptive transmission.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 15