Cerebral autoregulation is minimally influenced by the superior cervical ganglion in two- week-old lambs, and absent in preterm lambs immediately following delivery

Cerebral vessels in the premature newborn brain are well supplied with adrenergic nerves, stemming from the superior cervical ganglia (SCG), but their role in regulation of blood flow remains uncertain. To test this function twelve premature or two-week-old lambs were instrumented with laser Doppler...

Full description

Saved in:
Bibliographic Details
Published in:PloS one 2013-12, Vol.8 (12), p.e82326-e82326
Main Authors: Czynski, Adam J, Terry, Michael H, Deming, Douglas D, Power, Gordon G, Buchholz, John N, Blood, Arlin B
Format: Article
Language:English
Subjects:
Adrenergic nerves
Animals
Animals, Newborn
Blood
Blood flow
Blood Pressure
Blood vessels
Brain
Brain - blood supply
Brain - physiology
Cerebrovascular Circulation - physiology
Cesarean section
Circulatory system
Delivery, Obstetric
Electric Stimulation
Electrical stimuli
Flow resistance
Ganglia
Gestation
Hemoglobins - metabolism
Homeostasis
Hypertension
Nerves
Newborn babies
Perfusion
Premature Birth - physiopathology
Sheep, Domestic - physiology
Stimulation
Superior cervical ganglion
Superior Cervical Ganglion - physiology
Surgery
Veins & arteries
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Cerebral vessels in the premature newborn brain are well supplied with adrenergic nerves, stemming from the superior cervical ganglia (SCG), but their role in regulation of blood flow remains uncertain. To test this function twelve premature or two-week-old lambs were instrumented with laser Doppler flow probes in the parietal cortices to measure changes in blood flow during changes in systemic blood pressure and electrical stimulation of the SCG. In lambs delivered prematurely at ∼129 days gestation cerebral perfusion and driving pressure demonstrated a direct linear relationship throughout the physiologic range, indicating lack of autoregulation. In contrast, in lambs two-weeks of age, surgical removal of one SCG resulted in ipsilateral loss of autoregulation during pronounced hypertension. Electrical stimulation of one SCG elicited unilateral increases in cerebral resistance to blood flow in both pre-term and two-week-old lambs, indicating functioning neural pathways in the instrumented, anesthetized lambs. We conclude cerebral autoregulation is non-functional in preterm lambs following cesarean delivery. Adrenergic control of cerebral vascular resistance becomes effective in newborn lambs within two-weeks after birth but SCG-dependent autoregulation is essential only during pronounced hypertension, well above the normal range of blood pressure.
ISSN:1932-6203
1932-6203
DOI:10.1371/journal.pone.0082326