Fumihiko Sasaki

The effect of Cu2+ on rat pulmonary arterial rings

In the current study, Cu2+ was tested for its ability to relax vessels and to accumulate cyclic GMP (cGMP) in rat pulmonary artery employing rat extrapulmonary arterial rings. Cu(2+)-induced relaxation was endothelium and concentration (in the range from 10(-7) to 10(-4) M) dependent. The content of cGMP in the rings was increased 1.7-fold with 10(-4) M Cu2+. NG-Monomethyl-L-arginine abolished both the copper-induced relaxation and the increase in cGMP of rings. Cu2+ and zaprinast, which inhibits phosphodiesterase activity, caused a synergistic increase in cGMP level in the rings, suggesting that Cu2+ enhanced cGMP level through a mechanism different from that of zaprinast, probably as a consequence of elevated accumulation of nitric oxide (NO). The magnitude of vasorelaxation observed due to simultaneous addition of Cu2+ and acetylcholine was additive, not synergistic. Cu2+ did not augment relaxation induced by exogenously added NO donor. These results suggest that Cu2+ elevates NO level in the rings not by prolonging the half-life of NO, but by activation of endothelial nitric oxide synthase and subsequently potentiating the action of NO on vascular tone.

Effects of OK-432 on Bone Marrow Suppression due to Chemotherapy in Patients with Advanced Lung Cancer.

1) 進行肺癌症例に対する化学療法施行時にOK-432・5KE皮内投与 (週2～3回) を併用し, 骨髄抑制に対する効果を検討した.2) OK-432投与群では末梢血の白血球および顆粒球のNadirが非投与群と比較して有意に高かった.3) 小細胞肺癌例では化学療法施行後の血小板のNadirも非投与群と比較して有意に高かった.4) 白血球数2000/mm3未満, あるいは血小板数50000/mm3未1黄を示す症例はOK-432投与群で明らかに少なく, 更にその期間は短かった.5) 白血球のNadirから正常白血球数 (4000/mm3以上) に復するまでの期間はOK-432投与群が有意に短かった.