Functional significance of the dorsal respiratory group in adult and newborn rats: in vivo and in vitro studies

doi:10.1016/0304-3940(90)90357-F

Neuroscience Letters

Volume 111, Issues 1–2, 26 March 1990, Pages 133-138

https://doi.org/10.1016/0304-3940(90)90357-F Get rights and content

Abstract

The involvement of the dorsal part of the medulla (the so-called dorsal respiratory group: DRG) in the networks participating in respiratory function was investigated in newborn (in vitro) and adult (in vivo) rats. In the dorsal part of the medulla of the isolated brainstem of newborn rats, no respiratory neurons were found and stimulations or lesions neither modified nor suppressed the respiratory output. On the contrary, similar experiments suggest that sites in the ventral medulla have a fundamental importance for respiration. In adult rats, lesion of the DRG areas by electrocoagulation induced transient changes in respiratory timing, and resulted in a significant decrease in the amplitude of the contralateral phrenic output. These results suggest that the dorsal part of the medulla is not involved in controlling respiratory activity in the newborn rat. In adults, no definite conclusion can be reached, but the functional role of the DRG, if any, is probably restricted.

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The respiratory premotor neurons are located in the brainstem, mostly in the rostral ventral respiratory group (rVRG) (Dobbins and Feldman, 1994; Onai et al., 1987). In addition to the rVRG, a dorsal respiratory group (located in the NTS area) is also an important respiratory center in some species (for instance in cats), but its contribution is minor in rodents (Hilaire and Pasaro, 2003; Monteau et al., 1989; Hilaire et al., 1990, Ellenberger et al., 1990). Respiratory premotor neurons receive inputs from the pre-Bötzinger complex in the medulla, considered to be a key respiratory rhythm generator (Gray et al., 2001; Hilaire and Pasaro, 2003; Tan et al., 2008).
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Functional significance of the dorsal respiratory group in adult and newborn rats: in vivo and in vitro studies

Abstract

Brain Res.

Brain Res.

Resp. Physiol.

Neurosci. Lett.

J. Auton. Nerv. Syst.

Brain Res.

Brain Res.