Respiratory group

Compare and contrast functions of the dorsal and ventral respiratory groups in the medullary respiratory center... 

Opioids are potent respiratory depressants, causing a dose-dependent decrease in respiratory frequency, tidal volume and minute ventilation and increased arterial partial pressure of carbon dioxide (PaC02) (Carvey 1998). Opioids depress chemosensors in the brainstem, decreasing the ventilatory response to carbon dioxide. Opioids also depress rhythmicity in the dorsal respiratory group in the nucleus tractus solitarius, attenuating the respiratory cycle. Opioids, however, do not diminish hypoxic ventilatory drive. Significant elevations in Paco2 can result in increased ICP after opioid administration. 

Ellenberger, H. H., Feldman, J. L., and Zhan, W.-Z. (1990). Subnuclear organization of the lateral tegmental field in the rat. II Catecholamine neurons and ventral respiratory group. J. Comp. Neurol. 294, 212-222. 

RVL rostroventrolateral reticular nucleus 66, 68-71, 73-75, 83-84,90 RVRG rostral ventral respiratory group 70-75... 

Cl adrenaline cells Cl C2 adrenaline cells C2 C3 adrenaline cells C3 caudal interstitial nucleus of the medial longitudinal fasciculus Cl caudal linear nucleus of the raphe CLi caudal periolivary nucleus CPO caudate putamen (striatum) CPu caudoventral respiratory group CVRG caudoventrolateral reticular nucleus CVL cell bridges of the ventral striatum CB central amygdaloid nucleus, capsular part CeC... 

VENTRAL RESPIRATORY GROUPS AND B OTZINGER COMPLEX. These areas were delineated in accordance with Ellenberger et al. (1990), Kanjhan et al. (1995), and Cox and Halhday (1993). 

Poliacek I, Jakus J, Stransky A, Barani H, Halasova E, Tomori Z (2004) Cough, expiration and aspiration reflexes following kainic acid lesions to the pontine respiratory group in anesthetized cats. Physiol Res 53 155-163... 

Neurophysiological and neuroanatomical studies have selectively labeled the central projections of chemosensitive libers caudally to the obex within the NTS in cats and rats, whereas barosensory libers project rostral to the obex (57-59). The NTS, which contains the premotor neurons of the dorsal respiratory group (60), is now recognized as the major projection site of chemosensory libers. Neurons of caudal NTS with carotid chemoreceptor inputs project onto the ventrolateral medulla (61) that contains the premotor neurons of the ventral respiratory group (60). 

Takeda M, Matsumoto S. Discharge patterns of dorsal and ventral respiratory group neurons during spontaneous augmented breaths observed in pentobarbital anesthetized rats. Brain Res 1997 749 95-100. 

Fig. 63. Model representation of how a respiratory group is localized in the inner mitochondrial membrane. Above, side view below, cross-section. D = NAD", FP == flavoprotein, SD = flavoprotein of succinate dehydrogenase, b = cytochrome B complex, c = cytochrome C543 -H C544, a-fa3 = cytochrome oxidase complex. X, Y, Z = links to oxidative phosphorylation (modified from Lehninger 1969).

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