TY - JOUR
T1 - Differential effects of pentobarbital on intracerebral arterioles and venules of rats in vitro
AU - Ogura, K.
AU - Takayasu, M.
AU - Dacey, R. G.
PY - 1991
Y1 - 1991
N2 - The vasoactive properties of pentobarbital (PB) were studied in intracerebral arterioles and venules (diameter, 30-90 μm). These vessels mediate changes in cerebrovascular resistance and capacitance, respectively. Mean control vessel diameters of arterioles and venules at pH 7.3 were 53.9 ± 2.8 μm and 78.4 ± 4.3 μm, respectively. Both arterioles and venules dilated when the pH of the extraluminal solution was lowered to 6.8 and constricted when the pH was raised to 7.6. PB, 10-6 to 10-2 mol/L, dilated intracerebral arterioles in a dose-dependent manner at pH 7.3, reaching a maximal dilation of 129.7 ± 3.1% of control diameter at a dose of 10-3 mol/L. In contrast, PB at 10-6 to 10-2 mol/L failed to produce significant changes in the diameter of intracerebral venules. In addition, PB at 10-3 mol/L significantly inhibited arteriolar constriction induced by KCl (120 mmol/L), but not venular constriction. The present study suggests that intracerebral venules are relatively less responsive to PB than cerebral arterioles and peripheral veins. In addition to its effect on cerebral metabolism, PB may act to redistribute venous blood volume from cerebral veins to more responsive peripheral veins, thereby decreasing intracranial blood volume and intracranial pressure.
AB - The vasoactive properties of pentobarbital (PB) were studied in intracerebral arterioles and venules (diameter, 30-90 μm). These vessels mediate changes in cerebrovascular resistance and capacitance, respectively. Mean control vessel diameters of arterioles and venules at pH 7.3 were 53.9 ± 2.8 μm and 78.4 ± 4.3 μm, respectively. Both arterioles and venules dilated when the pH of the extraluminal solution was lowered to 6.8 and constricted when the pH was raised to 7.6. PB, 10-6 to 10-2 mol/L, dilated intracerebral arterioles in a dose-dependent manner at pH 7.3, reaching a maximal dilation of 129.7 ± 3.1% of control diameter at a dose of 10-3 mol/L. In contrast, PB at 10-6 to 10-2 mol/L failed to produce significant changes in the diameter of intracerebral venules. In addition, PB at 10-3 mol/L significantly inhibited arteriolar constriction induced by KCl (120 mmol/L), but not venular constriction. The present study suggests that intracerebral venules are relatively less responsive to PB than cerebral arterioles and peripheral veins. In addition to its effect on cerebral metabolism, PB may act to redistribute venous blood volume from cerebral veins to more responsive peripheral veins, thereby decreasing intracranial blood volume and intracranial pressure.
KW - Barbiturate
KW - Cerebral blood volume
KW - Cerebral microcirculation
KW - Intracranial pressure
KW - Vascular smooth muscle
UR - http://www.scopus.com/inward/record.url?scp=0025906808&partnerID=8YFLogxK
U2 - 10.1227/00006123-199104000-00009
DO - 10.1227/00006123-199104000-00009
M3 - Article
C2 - 2034348
AN - SCOPUS:0025906808
VL - 28
SP - 537
EP - 541
JO - Neurosurgery
JF - Neurosurgery
SN - 0148-396X
IS - 4
ER -