Korean J Physiol Pharmacol.  1998 Apr;2(2):193-199.

Contractile effects of hemoglobin-free human cerebrospinal fluid on isolated porcine cerebral arteries

• Baik YH
• Kang SY
• Kook H
• Chyung SK
• Kook YJ
• Kang SS

Abstract

To elucidate the mechanism involved in the cerebral vascular spasm following subarachnoid hemorrhage (SAH), the effects of the cerebrospinal fluid (CSF) obtained from the SAH patients on the resting tension and its influence on the contractile responses to various vasoactive agents and to hypoxia were investigated in isolated porcine cerebral arteries. All the CSFs containing hemoglobin (Hb) produced contraction and some Hb-free CSFs also elicited contraction. When the Hb-free CSF was separated by microfilter, the filtrate of < 30,000 MW did not produce contraction, while the fraction above 30,000 MW elicited more marked contractile responses than the unfractionated CSF. The CSF contraction was significantly attenuated in the presence of indomethacin or nimodipine, whereas the contractions induced by KCl, prostaglandin F2alpha (PGF2alpha), or endothelin-1 (ET-1) were not affected by the CSF pretreatment. However, the contractile responses induced by 5-hydroxytryptamine (5-HT) and phenylephrine (PE) were markedly potentiated by the pretreatment. Hypoxia-induced vasoconstriction was significantly potentiated by the pretreatment with either unfractionated CSF or the CSF fraction of above 30,000 MW. These
results
suggest that unknown vasocontractile substance(s) exists in the Hb-free CSF and that the substance, with its MW above 30,000, is activated by hypoxia and acts synergistically with 5-HT and PE, and that extracellular calcium influx and cyclooxygenase are also involved in the cerebral vasoconstrictory effect of Hb-free CSF.

Keyword

Subarachnoid hemorrhange; Cerebrospinal fluids; Isolated porcine cerebral artery; Hb-containing CSF, Hb-free CSF

MeSH Terms

Anoxia
Calcium
Cerebral Arteries*
Cerebrospinal Fluid*
Dinoprost
Endothelin-1
Humans*
Indomethacin
Nimodipine
Phenylephrine
Prostaglandin-Endoperoxide Synthases
Serotonin
Spasm
Subarachnoid Hemorrhage
Vasoconstriction
Calcium
Dinoprost
Endothelin-1
Indomethacin
Nimodipine
Phenylephrine
Prostaglandin-Endoperoxide Synthases
Serotonin