Objective: To examine the relation between the stimulation of the abdominal
sympathetic nervous system and vasospasm of the brain in eclamptic seizure
s, we analyzed brain blood flow after stimulation of the celiac ganglion by
lipopolysaccharide (LPS, 5, 50, or 500 mg/mL) or normal saline before and
after denovation of sympathetic trunk in pregnant and nonpregnant rats.
Methods: The brain blood flow was measured after stimulation of the celiac
ganglion with 50 mu L (5 mg/mL) LPS in group I, 50 mu L (50 mg/mL) LPS in g
roup II, 50 mu L Saline in group III, and 50 mu L (500 mg/mL) LPS (after de
novation of the sympathetic trunk) in group IV. A sham control experiment w
as also done by stimulation of the abdominal peritoneum with 50 mu L (500 m
g/mL) LPS in group V. Changes in water content and histological findings in
the brain were also studied in this protocol.
Results: A significant reduction in brain blood flow was observed in pregna
nt rats in groups I and II on stimulation of the celiac ganglion with LPS (
p < 0.0001, p < 0.001) compared with before stimulation. Celiac ganglion st
imulation with saline (group III) and LPS (group IV, after denovation of th
e sympathetic trunk) did not affect brain blood flow. Stimulation of the ab
dominal peritoneum with LPS (group V) could not induce any changes in brain
blood flow. Repeated seizures occurred in 60% of pregnant rats and a remar
kable increase in water content was observed after LPS stimulation of the c
eliac ganglion in groups I and II (p < 0.0001, p < 0.001). Histologically,
we found that stimulation of the celiac ganglion with LPS caused widening o
f perivascular spaces with compression of the vessels leading to ischemic c
hanges in brain tissues. There were no such findings observed in other grou
ps. However, a lesser extent effect was noticed in nonpregnant than seen in
pregnant rats.
Conclusion: Stimulation of the abdominal sympathetic ganglions could induce
vasoconstriction of the brain vessels, thus decreasing brain blood flow, w
hich results in eclampsialike changes in rats.