The role of medullary raphé serotonergic neurons in central chemoreception during sleep and wakefulness in newborn piglets

2003 ◽  
Author(s):  
Michelle L. Messier
Keyword(s):  
Serotonergic Neurons ◽  
Newborn Piglets ◽  
Medullary Raphe ◽  
Central Chemoreception

Inhibition of medullary raphé serotonergic neurons has age-dependent effects on the CO2 response in newborn piglets

2004 ◽  
Vol 96 (5) ◽  
pp. 1909-1919 ◽  
Author(s):  
Michelle L. Messier ◽  
Aihua Li ◽  
Eugene E. Nattie
Keyword(s):  
Cerebrospinal Fluid ◽  
Ventilatory Response ◽  
Sudden Infant Death ◽  
Sudden Infant ◽  
Serotonergic Neurons ◽  
Newborn Piglets ◽  
Artificial Cerebrospinal Fluid ◽  
Age Dependent ◽  
Medullary Raphe ◽  
Raphe Neurons

Medullary raphé serotonergic neurons are chemosensitive in culture and are situated adjacent to blood vessels in the brain stem. Selective lesioning of serotonergic raphé neurons decreases the ventilatory response to systemic CO2 in awake and sleeping adult rats. Abnormalities in the medullary serotonergic system, including the raphé, have been implicated in the sudden infant death syndrome ( 48 ). In this study, we ask whether serotonergic neurons in the medullary raphé and extra-raphé regions are involved in the CO2 response in unanesthetized newborn piglets, 3-16 days old. Whole body plethysmography was used to examine the ventilatory response to 5% CO2 before and during focal inhibition of serotonergic neurons by 8-hydroxy-2-di- n-propylaminotetralin (8-OH-DPAT), a 5-HT1A receptor agonist. 8-OH-DPAT (10 or 30 mM in artificial cerebrospinal fluid) decreased the CO2 response in wakefulness in an age-dependent manner, as revealed by a linear regression analysis that showed a significant negative correlation ( P < 0.001) between the percent change in the CO2 response and piglet age. Younger piglets showed an exaggerated CO2 response. Control dialysis with artificial cerebrospinal fluid had no significant effect on the CO2 response. Additionally, 8-OH-DPAT increased blood pressure and decreased heart rate independent of age ( P < 0.05). Finally, sleep cycling was disrupted by 8-OH-DPAT, such that piglets were awake more and asleep less ( P < 0.05). Because of the fragmentary sleep data, it was not possible to examine the CO2 response in sleep. Inhibition of serotonergic medullary raphé and extra-raphé neurons decreases ventilatory CO2 sensitivity and alters cardiovascular variables and sleep cycling, which may contribute to the sudden infant death syndrome.

1758-P: Type 2 Diabetes–Associated Mood Disorders: Role of Insulin Resistance in Serotonergic Neurons

Diabetes ◽  
2020 ◽  
Vol 69 (Supplement 1) ◽  
pp. 1758-P
Author(s):  
HUGO MARTIN ◽  
SÉBASTIEN BULLICH ◽  
FABIEN DUCROCQ ◽  
MARION GRALAND ◽  
CLARA OLIVRY ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Type 2 Diabetes ◽  
Mood Disorders ◽  
Serotonergic Neurons ◽  
P Type

scholarly journals Role of the medullary raphé in thermoregulatory vasomotor control in rats

2002 ◽  
Vol 540 (2) ◽  
pp. 657-664 ◽  
Author(s):  
Mutsumi Tanaka ◽  
Kei Nagashima ◽  
Robin M. McAllen ◽  
Kazuyuki Kanosue
Keyword(s):  
Vasomotor Control ◽  
Medullary Raphe

The role of the medullary raphe nuclei in regulation of cholinergic outflow to the airways

1998 ◽  
Vol 69 (1) ◽  
pp. 64-71 ◽  
Author(s):  
M.A. Haxhiu ◽  
B. Erokwu ◽  
V. Bhardwaj ◽  
I.A. Dreshaj
Keyword(s):  
Raphe Nuclei ◽  
Medullary Raphe ◽  
Raphé Nuclei

scholarly journals Role of Non-NMDA Receptors in the Hypoxia-Induced Increase in Extracellular Dopamine in Newborn Piglets. † 1737

1997 ◽  
Vol 41 ◽  
pp. 292-292
Author(s):  
Meng-Fai Kuo ◽  
Stephanie Murphy ◽  
Maria Delivoria-Papadopoulos ◽  
Anna Pastuszko
Keyword(s):  
Nmda Receptors ◽  
Newborn Piglets ◽  
Extracellular Dopamine

Role of serotonergic neurons in the maintenance of the 10-Hz rhythm in sympathetic nerve discharge

1996 ◽  
Vol 270 (1) ◽  
pp. R174-R181 ◽  
Author(s):  
H. S. Orer ◽  
M. E. Clement ◽  
S. M. Barman ◽  
S. Zhong ◽  
G. L. Gebber ◽  
...  
Keyword(s):  
Sympathetic Nerve ◽  
Peak Frequency ◽  
Inhibitory Effects ◽  
Receptor Agonists ◽  
Naturally Occurring ◽  
Medullary Raphe ◽  
Receptor Agonists And Antagonists ◽  
Raphe Neurons ◽  
Nerve Discharge

We studied the effects of serotonin (5-HT)-receptor agonists and antagonists on the naturally occurring 10-Hz rhythm in sympathetic nerve discharge (SND) of urethan-anesthetized, baroreceptor-denervated cats. Intravenous doses of the 5-HT1A-receptor agonists 8-hydroxy-2(di-n-propylamino)-tetralin (8-OH-DPAT) and U-93385E, which inhibit the firing of serotonergic medullary raphe neurons, decreased the power in the 10-Hz band of SND without affecting the power at frequencies < or = 6 Hz. The inhibitory effects of 8-OH-DPAT and U-93385E were reversed by the 5-HT1A-receptor antagonists spiperone and WAY-100135. Microinjection of 8-OH-DPAT into medullary raphe nuclei also selectively eliminated the 10-Hz rhythm in SND. Intravenous administration of the 5-HT2-receptor antagonist methysergide blocked the 10-Hz rhythm in SND, whereas the 5-HT2-receptor agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-amino-propane increased peak frequency and power in the 10-Hz band of SND. Microinjection of N-methyl-D-aspartic acid into the medullary raphe also enhanced the 10-Hz rhythm in SND. These data support the view that the naturally occurring discharges of serotonergic medullary raphe neurons preferentially enhance the 10-Hz rhythm in SND.

scholarly journals Role of serotonergic neurons in the Drosophila larval response to light

2009 ◽  
Vol 10 (1) ◽  
Author(s):  
Verónica G Rodriguez Moncalvo ◽  
Ana Regina Campos
Keyword(s):  
Serotonergic Neurons

The Role of Src Kinase in the Caspase-1 Pathway After Hypoxia in the Brain of Newborn Piglets

2014 ◽  
Vol 39 (11) ◽  
pp. 2118-2126 ◽  
Author(s):  
Dimitrios Angelis ◽  
Tania D. Fontánez-Nieves ◽  
Maria Delivoria-Papadopoulos
Keyword(s):  
Src Kinase ◽  
Newborn Piglets ◽  
Caspase 1 ◽  
The Brain

Hypoglycemia selectively abolishes hypoxic reactivity of pial arterioles in piglets: role of adenosine

1995 ◽  
Vol 268 (2) ◽  
pp. H871-H878 ◽  
Author(s):  
T. S. Park ◽  
E. R. Gonzales ◽  
A. R. Shah ◽  
J. M. Gidday
Keyword(s):  
Arterial Pco2 ◽  
Adenosine Receptor Antagonist ◽  
Cranial Window ◽  
Newborn Piglets ◽  
Window Technique ◽  
Pial Arterioles ◽  
Cerebrovascular Regulation ◽  
Arterial Po2 ◽  
Arteriolar Diameter

Episodes of hypoxia often occur in hypoglycemic newborns, but it is not known whether dysfunctions in cerebrovascular regulation contribute to brain injury incurred by these affected neonates. We tested the hypotheses that 1) perinatal hypoglycemia impairs cerebrovascular responses to hypoxia and 2) a reduced vascular smooth muscle sensitivity to adenosine accounts for this impairment. Responses of 25- to 50-mu m-diam pial arterioles were determined using the cranial window technique in isoflurane-anesthetized newborn piglets < 5 days of age. Hypoxia (arterial PO2 = 28 +/- 1 mmHg) caused a 47 +/- 5% increase (P = 0.0008) in arteriolar diameter, 89% of which could be blocked by prior superfusion of the window space with the preferential A2-adenosine receptor antagonist 3,7-dimethyl-1-propargylxanthine (DMPX; 50 microM). Insulin-induced hypoglycemia (blood glucose = 18 +/- 1 mg/dl without isoelectric electroencephalogram) caused a 31 +/- 5% increase (P = 0.002) in arteriolar diameter; however, no additional dilatative response to hypoxia (arterial PO2 = 28 +/- 1 mmHg) could be elicited in these animals. Arteriolar dilation of 41 +/- 6% (P = 0.002) induced by superfusion of 20 microM adenosine under normoglycemic conditions was also completely abolished after the animals were rendered hypoglycemic. Unlike the response to hypoxia and adenosine, hypoglycemia only attenuated prostanoid-dependent dilations to hypercapnia (arterial PCO2 = 68 +/- 3 mmHg) by 55 +/- 9%. These results indicate that, in the newborn, hypoglycemia selectively abolishes hypoxic reactivity through an impairment in adenosine-mediated cerebrovascular dilation.

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