破裂脳動脈瘤患者における髄液c-AMP濃度の経時的変化

SEQUENTIAL CHANGES OF C-AMP CONCENTRATION IN CSF FOLLOWING RUPTURE OF CEREBRAL ANEURYSM

I．はじめに

　脳梗塞，脳出血等の脳血管障害患者，急性期頭部外傷患者，および，てんかん患者などの髄液cyclic adeno—sine monophosphate〔c-AMP〕濃度について，その測定手技の確立に伴い，最近いくつかの報告がなされて来ており，その解釈についても種々論議されている。しかし脳動脈瘤破裂症例における髄液c-AMP濃度についての報告は少い。今回，我々は脳動脈瘤破裂によるくも膜下出血患者の髄液c-AMP濃度を測定し，その経時的変化をみると共に，更に髄液血性度，髄液圧，臨床症状，脳血管写所見，および平均脳血流量との関連をも検討し若干の知見を得たので報告する。

Cyclic adenosine-3', 5'-monophosphate [c-AMP] concentration in lumbar cerebrospinal fluid [CSF] was measured by radioimmunoassay in 65 samples of 28 patients with ruptured cerebral aneurysm. Control level of c-AMP in CSF obtained from 8 cases with low CSF syndrome was 14.2± 3.0 [mean ±S. D.] pmoles/ml.

1) In the patients following subarachnoid hemor-rhage [SAH] c-AMP concentration was varied from 6.6 to 80 pmoles/ml and, for the most part, higher than the control. Sequentially, it retained the control level within 4 days, then increased in various degree and made a peak about 10 days, and returned to the control level about 30 days after SAH. This characteristic sequential change showed a close resemblance to that of the cerebral vaso-spasm after SAH.

2) During 5 to 20 days after SAH, high level of c-AMP concentration correlated well with the severity of clinical grade by Hunt & Hess. Grade I, II ; 23.8±8.2, Grade III ; 37.5±13.5, Grade IV ; 50.1±22.4 pmoles/ml, respectively. Within 4 days and over 30 days, however, it remained control range almost with no correlation to the clinical grade.

3) High c-AMP concentration during 5 to 20 days after SAH had a good correlation to cerebral vasospasm ; 30.5±10.1 pmoles/ml and 20. 1±6. 6 pmoles/ml, with and without diffuse vasospasm, respectively.

4) There was negative correlation [r= -0.69] between mean cerebral blood flow and c-AMP concentration.

5) These results suggest that the increase of c-AMP concentration in CSF after SAH is associated with extracellular c-AMP accumulation due to im-paired cellular function and/or abnormal neuro-transmitter release in the ischemic brain following cerebral vasospasm, and that c-AMP level in CSF may indicate the activity of the pathological process in the brain after SAH.