Tadashi Nishimoto

Cyclic Adenosine Monophosphate Production and Contractile Response Induced by Beta-Adrenoceptor Subtypes in Rabbit Urinary Bladder Smooth Muscle

The spontaneous contractile force of muscle strips isolated from male rabbit urinary bladder dome [detrusor) and base (trigonal muscle) was dose dependently inhibited by isoproterenol, a non-specific beta-adrenoceptor agonist. The relaxant response to 10(-6) M isoproterenol in the detrusor muscle was completely blocked by butoxamine (10(-4) M), a selective beta-2-antagonist, and by propranolol (10(-6) M), a non-specific beta-antagonist, but not by metoprolol (10(-6) to 10(-4) M), a selective beta-1-antagonist. Relaxation of trigonal muscle induced by 10(-6) M isoproterenol was inhibited 30% by metoprolol (10(-5) M), 70% by butoxamine (10(-4)M), and 100% by propranolol (10(-6) M). Terbutaline, a selective beta-2-adrenoceptor agonist, also caused dose dependently a relaxant response in detrusor and trigonal muscle. The maximum relaxant responses to isoproterenol and terbutaline were significantly greater in detrusor than in trigonal muscle. Dobutamine, a relatively specific beta-1-adrenoceptor agonist, caused a small but significant relaxant response in trigonal, but no change in detrusor muscle. In trigonal muscle the relaxant response to dobutamine was less than that to terbutaline. Cyclic adenosine monophosphate accumulation in detrusor did not significantly increase after administration of dobutamine, but significantly increased after administration of terbutaline. On the other hand, not only terbutaline, but also dobutamine, markedly increased cyclic adenosine monophosphate accumulation in trigonal muscle.(ABSTRACT TRUNCATED AT 250 WORDS)

Chemosensitivity of human bladder cancer cells in long-term culture and clinical responses to the selected anticancer drug

In vitro sensitivity of an established cell line from human urinary bladder cancer to various chemotherapeutic agents was determined by 14C‐leucine incorporation into the target cells. Of 12 drugs tested, Carboquone, Neocarzinostatin, Actinomycin D, Adriamycin, Mitomycin C and Chromomycin A3 produced intensive cytotoxic effects, while Thio‐Tepa, Bleomycin, 5‐Fluorouracil and Vincristine were less cytotoxic. Intravesical instillation of Carboquone, one of the most toxic agents in vitro, resulted in complete or partial tumor remission in 6 of 9 patients with bladder cancer. Prophylactic effects of periodic intravesical Carboquone were also indicated in 7 of 8 patients who had experienced recurring superficial bladder tumors.

Clinical evaluation of bicarbonate dialysis

重炭酸透析については, 最近いくつかの報告がなされており, 酢酸透析に比較し不快な症状の少ない透析ができる点で, その有効性が見直されている. 今回我々は, 透析時間を5時間から4時間に短縮し, 透析効果について5時間の酢酸透析と比較し検討を加えた.その結果, pH, HCO-3濃度, B. E. は, 4時間透析にもかかわらず酢酸透析に比較し透析後有意に上昇し, アシドーシスの改善効果が優れていた. 特にpHの改善が顕著で, 透析開始2時間で7,332±0.026から7.403±0.04まで上昇していた.尿素窒素, クレアチニン, 尿酸値は, 透析後有意に低下し, 除去率では, 5時間の酢酸透析と比較し劣らない結果を得た. 特にクレアチニンの除去率は, 酢酸透析の44.1±6.4%に比し, 重炭酸透析では, 52.7±4.4%と有意に高値を示した. また長期的にみた窒素代謝産物の透析前値の上昇, 及び体重の増加はまったく認められなかった. 透析ごとの体重減少量の比較では, 酢酸透析で2.0±0.4kg, 重炭酸透析で23±0.3kgと両者間に有意の差をみなかった. Ca濃度については, 透析後有意に上昇し, 低Ca血症は改善されていた.以上の所見より, 重炭酸透析では, 酸-塩基平衡の改善が効率よくしかも迅速であり, 透析中の不快な症状が少ないばかりでなく, 透析終了時まで十分な血液流量, 及び適正な限外濾過圧を維持することができ, 今後大面積-短時間透析において非常に有利であると判断した.