Cardiorespiratory effects of l-glutamate microinjected into the rat ventral medulla

Tolentino‐Silva, Fatima; Campos, Rui; Russo, Adriana Kowalesky; Cravo, Sérgio L.; Lopes, Oswaldo Ubrı́aco

doi:10.1016/s0034-5687(97)02530-9

Cited by 12 publications

(14 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the present study ventral landmarks have been linked with ventrally located functional sites. The use of ventral surface Tolentino-Silva et al, 1997) or dorsal surface (Sved et al, 2000;Willette et al, 1983) landmarks, particularly the obex and calamus scriptorius, to provide location coordinates can be problematic as they vary substantially depending upon the orientation used e.g. flat skull versus flat dorsal medullary surface or angled placement of pipettes (see also Schreihofer and Guyenet, 2002) and histological processing.…”

Section: Discussionmentioning

confidence: 99%

Maps of cardiovascular and respiratory regions of rat ventral medulla: Focus on the caudal medulla

Goodchild

Moon

2009

Journal of Chemical Neuroanatomy

View full text Add to dashboard Cite

Section: Discussionmentioning

confidence: 99%

Maps of cardiovascular and respiratory regions of rat ventral medulla: Focus on the caudal medulla

Goodchild

Moon

2009

Journal of Chemical Neuroanatomy

View full text Add to dashboard Cite

“…Topical application to (12) or microinjections (9,13) of L-glutamate into the ventrolateral medullary surface elicit pronounced changes in respiration and arterial blood pressure. In a previous study (9) we demonstrated that, in the rat, three different breathing patterns could be elicited from four distinct sites within the VMS. When applied to the RVL or the CPA, L-glutamate produced increases in ventilation, inspiratory drive and hypertension.…”

mentioning

confidence: 88%

“…Our study demonstrated that in this area even unilateral blockade of glutamatergic afferents is capable of producing significant reductions in ventilation. Contrarily, in caudal portions of the VMS (including the caudal respiratory area overlapping the caudal ventrolateral medulla and the caudal pressor area) unilateral glutamatergic blockade was unable to modify respiration, even though these areas are responsive to glutamate stimulation (9).…”

mentioning

confidence: 97%

“…The RVL overlaps most of the intermediate area, whereas CVL overlaps the caudal respiratory area. Although CPA stimulation produces a well-defined respiratory activation (9), so far this response has not been related to any particular respiratory area.…”

mentioning

confidence: 99%

“…To further identify injection sites, the brainstem was also cut coronally into 40-µm thick sections and stained with 1% neutral red. Photomicrographs and schematic drawings of typical injection sites obtained with this method have been presented elsewhere (9). The breath-by-breath respiratory pattern data for each animal were interpolated at 15-s intervals.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Respiratory effects of kynurenic acid microinjected into the ventromedullary surface of the rat

Tolentino-Silva

Russo

Cravo

et al. 1998

Braz J Med Biol Res

View full text Add to dashboard Cite

Several studies demonstrate that, within the ventral medullary surface (VMS), excitatory amino acids are necessary components of the neural circuits involved in the tonic and reflex control of respiration and circulation. In the present study we investigated the cardiorespiratory effects of unilateral microinjections of the broad spectrum glutamate antagonist kynurenic acid (2 nmol/200 nl) along the VMS of urethaneanesthetized rats. Within the VMS only one region was responsive to this drug. This area includes most of the intermediate respiratory area, partially overlapping the rostral ventrolateral medulla (IA/RVL). When microinjected into the IA/RVL, kynurenic acid produced a respiratory depression, without changes in mean arterial pressure or heart rate. The respiratory depression observed was characterized by a decrease in ventilation, tidal volume and mean inspiratory flow and an increase in respiratory frequency. Therefore, the observed respiratory depression was entirely due to a reduction in the inspiratory drive. Microinjections of vehicle (200 nl of saline) into this area produced no significant changes in breathing pattern, blood pressure or heart rate. Respiratory depression in response to the blockade of glutamatergic receptors inside the rostral VMS suggests that neurons at this site have an endogenous glutamatergic input controlling the respiratory cycle duration and the inspiratory drive transmission.

show abstract

Respiratory Rhythm Generation: Prebötzinger Neuron Discharge Patterns and Persistent Sodium Current

McCrimmon¹,

Monnier²,

Ptak³

et al. 2001

Advances in Experimental Medicine and Biology

View full text Add to dashboard Cite

Cardiorespiratory effects of l-glutamate microinjected into the rat ventral medulla

Cited by 12 publications

References 21 publications

Maps of cardiovascular and respiratory regions of rat ventral medulla: Focus on the caudal medulla

Maps of cardiovascular and respiratory regions of rat ventral medulla: Focus on the caudal medulla

Respiratory effects of kynurenic acid microinjected into the ventromedullary surface of the rat

Respiratory Rhythm Generation: Prebötzinger Neuron Discharge Patterns and Persistent Sodium Current

Contact Info

Product

Resources

About