Effect of chemical stimulation of the dorsal raphe nucleus on cerebral blood flow in rat

1995 ◽  
Vol 199 (3) ◽  
pp. 228-230 ◽  
Author(s):  
Mark D. Underwood ◽  
Mihran J. Bakalian ◽  
Victoria Arango ◽  
J. John Mann
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Dorsal Raphe Nucleus ◽  
Dorsal Raphe ◽  
Chemical Stimulation ◽  
Raphe Nucleus ◽  
Dorsal Raphé ◽  
Stimulation Of

scholarly journals Effects of Electrical Stimulation of the Dorsal Raphe Nucleus on Local Cerebral Blood Flow in the Rat

1989 ◽  
Vol 9 (3) ◽  
pp. 251-255 ◽  
Author(s):  
G. Bonvento ◽  
P. Lacombe ◽  
J. Seylaz
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Electrical Stimulation ◽  
Dorsal Raphe Nucleus ◽  
Brain Structures ◽  
Dorsal Raphe ◽  
Raphe Nucleus ◽  
Local Cerebral Blood Flow ◽  
Dorsal Raphé ◽  
Stimulation Of

We have studied the effects of electrical stimulation of the dorsal raphe nucleus on local cerebral blood flow (LCBF), as assessed by the quantitative [14C]-iodoantipyrine autoradiographic technique. Stimulation of the dorsal raphe nucleus in the α-chloralose anesthetized rat caused a significant decrease in LCBF, ranging from – 13 to – 26% in 24 brain structures out of 33 investigated. The most pronounced decreases (– 23 to – 26%) were observed in the accumbens, amygdaloid, interpeduncular nuclei and in the median raphe nucleus, limbic system relays. The decreases also concerned cortical regions and the extrapyramidal system. These results indicate that activation of ascending serotonergic system produces a vasoconstriction and that the dorsal raphe nucleus has a widespread modulatory influence on the cerebral circulation.

scholarly journals Regulation of Cortical Blood Flow by the Dorsal Raphe Nucleus: Topographic Organization of Cerebrovascular Regulatory Regions

1992 ◽  
Vol 12 (4) ◽  
pp. 664-673 ◽  
Author(s):  
Mark D. Underwood ◽  
Mihran J. Bakalian ◽  
Victoria Arango ◽  
Robert W. Smith ◽  
J. John Mann
Keyword(s):  
Heart Rate ◽  
Blood Flow ◽  
Arterial Pressure ◽  
Dorsal Raphe Nucleus ◽  
Dorsal Raphe ◽  
Raphe Nucleus ◽  
Cortical Blood Flow ◽  
Response To Change ◽  
Dorsal Raphé ◽  
Stimulation Of

We examined in rat: (1) the time-course and magnitude of change in cortical blood flow (CoBF) following electrical stimulation of the dorsal raphe nucleus (DRN) and (2) whether DRN lesions affect resting CoBF or the cerebrovascular response to CO2. Animals were anesthetized (chloralose), paralyzed, and artificially ventilated. The effect of stimulus frequency (1–200 Hz) and intensity (10–100 μA) on arterial pressure, heart rate, and CoBF was examined; lesions were made electrolytically. CoBF was measured using a laser-Doppler flowmeter with the probe placed extradurally over the parietal sensorimotor cortex. The DRN was computer reconstructed in three dimensions from Nissl stained coronal sections for localization of electrode placements. Brief stimuli (8 s; n = 6) elicited frequency and intensity-dependent increases in arterial pressure, heart rate, and CoBF. Sustained intermittent trains of stimuli of rostral DRN (200 Hz; 1 s on/1 s off; 70 μA) elicited a decrease (85 ± 12% of baseline; n = 9) in CoBF ( p < 0.05) while stimulation in caudal DRN resulted in increased CBF (126 ± 13% of baseline; n = 9). Phenylephrine infusion (0.1–1 μg; i.v.; n = 8) increased arterial pressure and CoBF less than that elicited by brief DRN stimulation ( p < 0.05). DRN lesions did not affect resting CoBF (140 ± 25 perfusion units (PU) before; 127 ± 16 PU after DRN lesion; p > 0.05, n = 5) or mean arterial pressure (127 ± 13 before; 120 ± 11 after); nor did it affect the cerebrovascular response to change in arterial Pco2. Sustained intermittent stimulation of the DRN can evoke either increases or decreases in CoBF depending on the anatomical sublocalization. The DRN does not tonically maintain resting CoBF, nor participate in the cerebrovascular response to change in Pco2.

Effects of dorsal raphe nucleus stimulation on cerebral blood flow and flow-metabolism coupling in the conscious rat

Neuroscience ◽  
1993 ◽  
Vol 55 (2) ◽  
pp. 395-401 ◽  
Author(s):  
A. Cudennec ◽  
G. Bonvento ◽  
D. Duverger ◽  
P. Lacombe ◽  
J. Seylaz ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Dorsal Raphe Nucleus ◽  
Dorsal Raphe ◽  
Raphe Nucleus ◽  
Conscious Rat ◽  
Dorsal Raphé

scholarly journals Differential Effects of Electrical Stimulation of the Dorsal Raphe Nucleus and of Cervical Sympathectomy on Serotonin and Noradrenaline Concentrations in Major Cerebral Arteries and Pial Vessels in the Rat

1990 ◽  
Vol 10 (1) ◽  
pp. 123-126 ◽  
Author(s):  
G. Bonvento ◽  
P. Lacombe ◽  
E. T. MacKenzie ◽  
L. Rouquier ◽  
B. Scatton ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Dorsal Raphe Nucleus ◽  
Cerebral Arteries ◽  
Dorsal Raphe ◽  
Raphe Nucleus ◽  
Cervical Sympathectomy ◽  
Large Arteries ◽  
Pial Vessels ◽  
Dorsal Raphé ◽  
Stimulation Of

The levels of noradrenaline (NA), serotonin (5-HT), and 5-hydroxyindoleacetic acid were measured by HPLC and compared between the large arteries of the circle of Willis and the small pial vessels in the rat, following either electrical stimulation of the dorsal raphe nucleus or bilateral superior cervical ganglionectomy. With electrical stimulation, the 5-HT concentrations were reduced (– 48%) in the small pial vessels, but were unchanged in the major cerebral arteries. NA concentrations were dramatically reduced following cervical sympathectomy in the large arteries (– 77%), though the reduction was less pronounced (– 34%) in the small vessels. Sympathectomy caused a significant decrease in the 5-HT concentration of the major cerebral arteries (–33%), but was without effect on the 5-HT levels of the small pial vessels. These results show that an appreciable fraction of the perivascular 5-HT measured in the small pial and the large cerebral arteries originates from different sources.

Sign in / Sign up

Export Citation Format

Share Document