Kazuyo Kamiyama

Measurement of regional blood flow using hydrogen gas generated by electrolysis.

Electrochemically generated hydrogen gas was used to measure local blood flow by Stosseck et al. The data obtained by their method, however, did not correlate well with those obtained by hydrogen inhalation. We have modified the equation proposed by Stosseck, prolonging the stimulus duration in order to increase the amount of hydrogen generated. In dog white matter the resulting clearance curves were formed to be monoexponential both in the living animal as well as after circulatory arrest when all the clearance is by diffusion away from the electrode. The values calculated by our equation correlated well with those obtained by hydrogen inhalation.

The Activities of Phospholipase Al, A2, Lysophospholipase and Acyl CoA: Lysophospholipid Acyltransferase in Ischemic Dog Brain

Biomembranes play an extremely important role in maintaining normal energy production in the cell and in the transport of essential molecules. The individual components of the cellular membrane itself are not stable, but rather undergo continuous turnover while maintaining homeostasis. Phospholipids are an important element in these membranes and particularly in the brain where membraneous structures are numerous, they constitute a large volume. The metabolism of brain phospholipid is consequently a topic of great interest.

Relation of supersensitivity to cerebral vasospasm induced by oxyhaemoglobin

There have been reports that superior cervical ganglionectomy (SCG) is effective as a treatment for cerebral vasospasm following subarachnoid haemorrhage (SAH). On the other hand, denervation supersensitivity is supposed to play an important role in vasospasm. The two accounts contradict each other. To investigate this problem, various examinations were performed using the exposed basilar arteries of cats. We have accepted that oxyhaemoglobin (Oxy-Hb) is an important spasmogenic substance. Therefore, the change in vascular reactivity to Oxy-Hb was investigated after various kinds of denervations. It was confirmed that Oxy-Hb has no adrenergic receptor agonist properties because the Oxy-Hb inducing vasospasm was not suppressed by Prazosin or phenoxybenzamine. As a result of this, it is not likely that augmentation of Oxy-Hb inducing vasospasm is caused by deviation supersensitivity. Thus, the non-deviation supersensitivity became a topic of investigation. The basilar arteries were denervated by chemical treatment (reserpine, 6-hydroxydopamine) or bilateral SCG to examine the change in the reactivity to noradrenaline or Oxy-Hb. An increase in reactivity to noradrenaline was observed with the denervations. In contrast, no change in reactivity to Oxy-Hb was found. In conclusion, it was observed that deviation and non-deviation supersensitivity do not participate in vasospasm, in so far as vasospasm is caused by Oxy-Hb.

Membranous stenotic lesion in the cervical carotid artery in a young woman. Case report.

症例は31歳女性, 頭部外傷による頭痛を主訴として受診した.神経学的所見に異常を認めなかったが, CTで左Sylvius裂にクモ膜下出血の所見を認めた.さらに脳血流測定にて, 右大脳半球の血流低下所見を認めたため, 脳血管撮影を施行したところ, 右頚部内頚動脈分岐部に膜状の狭窄病変を認めた.他の脳血管に動脈硬化性変化を示唆する所見は認められなかった.虚血発作予防を目的として, 病変部を含む内膜切除術を施行した.病変部は血管内壁に連続するうすい膜状の病変で, 血管腔の約70%を狭窄していた.周囲の動脈に動脈硬化性病変は認めなかった.病理所見は動脈硬化のfibrous plaqueと同様であったが, 患者の年齢が若いこと, 病変がきわめて限局していること, 他の血管に病変を認めないことから, 通常の動脈硬化とは異なる病変と考えられた.本病変の発生機序と意義につき若干の考察を加え報告する.