H Onimaru

..Our findings suggested that the location of Phox2b-ir neurons, including preinspiratory neurons of the pFRG, matched their role as sensors of blood CO(2) concentration...

..These neurons were predominantly Phox2b immunoreactive. Our findings suggest that the response of pFRG/RTN neurons to hypercapnia is induced by direct action on the postsynaptic membrane via closing of K(+) channels...

..These results show that the rostral medulla, not including the pre-Bötzinger complex, produces Pre-I-like rhythmic activity that can be monitored as facial nerve motor output in newborn rat in vitro preparations...

..This rhythmic burst activity may be involved in the development of neuronal circuits that process information related to olfaction, emotion, and respiration...

..Coupling was partially restored by repeated activation of the neurons within the networks, suggesting the involvement of an activity-dependent process in the prenatal development of this coupling...

..We show two different modes of respiratory rhythm generation in the brainstem-spinal cord preparation that depends on the background stimulation level...

..Our findings suggest that Phox2b-expressing parafacial neurons play a role in respiratory rhythm generation as well as central chemoreception and thus are essential for postnatal survival...

..In this brief review, we focused on these recent findings and discuss the functional role of pFRG/Pre-I neurons...

..Here, we briefly review these recent findings. We also show a unique distribution of Phox2b expressing cells in the most rostral medulla, which could be an interesting target for neurophysiological analysis...

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..We show that usage of calcium imaging would be very useful for analysis of neuronal activity over different time scales, and discuss the advantages and disadvantages of this method...

..Potentiation of synaptic interaction between respiratory neurons, causing developmental changes in the burst pattern, might be involved in the maturation process during late fetal stages...

..Our findings suggest that the pFRG comprises a neuronal population that is involved in the primary respiratory rhythm generation in the rostrocaudally extending respiratory neuron network of the medulla...

..Such an activity pattern was not clearly detected in Pbx3-/- mouse preparations. The difference in the spatio-temporal pattern between Tlx3-/- and Pbx3-/- suggests different levels of functional disorder of the respiratory center...

..We suggest that the pre-inspiratory neuron network of the para-facial region in the rostral ventrolateral medulla functions as the rhythm generator after E19/20...

..This method is very useful for analysis of pharmacological properties, as well as the spatio-temporal pattern of respiratory-related network activity in the brainstem...

..The increase in EPSPs of the IML neurons in response to glutamate application suggests that the CeVLM participates in the regulation of sympathetic nerve activity and blood pressure and may correspond to the caudal pressor area...

..Thus, pre-inspiratory neurons might play an important role in modulation of respiratory rhythm by central chemoreception in the brainstem-spinal cord preparation...

..These differences in RVLM neurons suggest a mechanism that possibly leads to elevation in blood pressure...

..9+/- 4.0 sec vs. 4.7+/- 2.1 sec, P> 0.01). Our results suggest that administration of an appropriate dose of cannabinoid receptor agonist WIN 55,212-2 has an anticonvulsant effect but does not cause respiratory depression...

..We hypothesize that modulation of spontaneous activity of pre-inspiratory neurons via N-, L- and P/Q-type Ca2+ channels is important for respiratory rhythm or pattern generation...

..Our findings also suggest the existence of a pontine excitatory system, which is depressed by the pontine inhibitory system under control conditions...

..We propose that the same pathway is responsible for rhythmic activation of the abdominal muscles during opioid-induced apnoea in the newborn rat...

..These results suggest that the angiotensin II type 2 receptor in rostral ventrolateral medulla plays an antagonistic role against the angiotensin II type 1a receptor in controlling the neuronal activity of rostral ventrolateral medulla...

..Finally, excess GABA-mediated inhibition caused dysfunction of central respiratory circuits in Tlx3 mutant mice...

..Pbx3-deficient mice provide a model for congenital central hypoventilation syndrome and suggest that Pbx3 mutations may promote the pathogenesis of this disorder...

..The results explain the mechanism by which Ang II in the RVLM area increases peripheral sympathetic activity and blood pressure...

..Based on these results, we propose a model for functional coupling between the Na+, K+-ATPase alpha2 subunit and KCC2, which excludes Cl- from the cytosol in respiratory center neurons...