An automatic adder mixer for photometric cells was newly developed in our laboratory and was applied in experiments of superprecipitation of myosin B. The mixer has a reciprocating blade-type impeller with a pit for loading samples. The pit was cut so as to be just above the meniscus of the solution in a cell at the top dead point of the cam mechanism and so as to enter the solution at the bottom dead point. When 10 μl of methylene blue solution was added, the mixing time was 0.6 sec. Myosin B was extracted from rabbit white muscle. Adding ATP (1 mM) to myosin B suspension and mixing was carried out by hand, using a mixing plunger, and also using the automatic adder mixer. The recordings obtained were then compared. Continuous recording of the initial reaction was successfully obtained only when the automatic adder mixer was used. Excellent results were also obtained with respect to reproducibility. The automatic adder mixer is easy to make, inexpensive, and can be utilized in conjunction with conventional spectrophotometers.

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Effects of diethyldithiocarbamate(DDC) on erection and ejaculation were investigated and monoamine levels in central nervous system, gonad and accessory glands were determined in dogs. Intraperitoneal administration of 50, 75 and 100 mg/kg of DDC suppressed ejaculation 1 hour after administration, although penial erection did occur. This suppression of ejaculation was recovered to some extent 3 hours after DDC and completely recovered 24 hours after DDC. One hour after the administration of 100 mg/kg of DDC, noradrenaline (NA) level in the caudate and serotonin (5-HT) level in the posterior hypothalamus decreased significantly, as compared with the control. However, there were no significant changes in the regions of anterior hypothalamus and hippocampus which are known to play an important role in sexual behavior. In the epididymis, NA and adrenaline levels decreased significantly, though 5-HT levels increased, as compared with those of the control. In the prostate and posterior urethra, NA levels decreased significantly, as compared with the control. The seminal emission induced by hypogastric nerve stimulation induced a gradual rise in the posterior urethral pressure. When the pressure reached the maximum level, rhythmic alterations of the pressure considered to be a phenomenon associated with ejaculation occurred. DDC (100 mg/kg) abolished both seminal emission and rhythmic alterations of the posterior urethral pressure. These findings indicate that the sperm transport may be inhibited by decrease of NA level in accessory glands.

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Effects of oral administration of tiopronin (2-mercaptopropionylglycine) on acute liver damage induced in rats by intraperitoneal administration of carbon tetrachloride (CCl₄) were investigated. Tiopronin suppressed increase in serum transaminase activity, accumulation of liver triglyceride and decrease of liver glucose-6-phosphatase activity induced by CCl₄. CCl₄ induced a significant decrease of nonprotein thiol (NPSH) in the liver 24 hr after administration, but this decrease did not result in an increase of nonprotein disulfide in the liver. Tiopronin suppressed the decrease in NPSH induced by CCl₄, but did not influence NPSH in normal rats 24 hr after administration. In addition to these biochemical findings, it was also noted that tiopronin prevented necrosis and decrease of glycogen in liver, as determined histologically. Other compounds such as cystamine, cysteine and glutathione proved to have a preventive effect on CCl₄-induced liver damage as in the case of tiopronin. It was revealed that such preventive effect correlated to some extent with NPSH content in liver as well as serum transaminase activity and histological findings.

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Effect of tolmetin sodium(Tol) on acute and subacute exudative inflammation was tested in experimental animals. Tol had a potent inhibitory activity(ED50=0.75 mg/kg, p.o.) on the increased vascular permeability induced by acetic acid in mice, and the potency was about 0.4 times that of indomethacin(Ind), and 6-93 times that of ibuprofen(Ibu), phenylbutazone(Phe) and aspirin(Asp). The inhibitory activity of Tol(ED50=18.2 mg/kg, p.o.) on UV-induced erythema in guinea pigs was about 0.3 times that of Ind. A recovery of the hind paw edema of rats, produced by a mixture of kaolin and carrageenin, was promoted by oral administration of Tol (2.5 ?? 20 mg/kg×5/2 days). Tol(80 mg/kg/day, p.o.) showed a significant activity in inhibiting the exudation caused by croton oil in rats, and the activity was about 0.025 times that of Ind and greater than that of Ibu, Phe and Asp. Tol(100-800 μg/ml) inhibited in a dose-dependent manner the phytohemagglutinin-induced blast transformation of cultured lymphocytes from rat thymus, as did salicylic acid. In vitro, Tol showed a potent activity similar to that of Ibu and Phe in preventing the denaturation of bovine serum albumin and the lysis of rat erythrocytes. From these results, it is suggested that Tol has a particularly potent inhibitory activity on acute exudative inflammation, and the mode of action may be attributed to a mechanism similar to that seen with other acidic non-steroidal anti-inflammatory drugs.

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Effect of dialysate from buckwheat extract on immediate hypersensitivity reactions. To investigate the hypersensitivity reaction of buckwheat, the aqueous extract of buckwheat was separated into dialysate (BWD) and non-dialysate (BWND). BWD neither decreased a release of anaphylactic mediator from the chopped lung tissue nor inhibited Schultz-Dale reaction in the ileum of guinea pig sensitized with BWND. Heterologous PCA mediated by rabbit anti-BWND serum in guinea pig and homologous PCA in rats using anti-BWND IgE serum were inhibited by i.d. or i.v. treatment of BWD. Radioallegosorbent test (RAST) and PK reaction were inhibited in a dose dependent fashion by BWD mixed with human serum sensitive to buckwheat, although BWD required approximately 10, 000 times more than BWND to produce a RAST inhibition. RAST, however, was not affected when BWD was added to ¹²⁵I-labelled anti-human IgE. Anti-buckwheat IgE antibody in sensitized animals and atopic patients was specifically absorbed with an insoluble copolymer of BWD-conjugated BSA. BWD did not form a precipitin line against anti-BWND IgG antibody in immunoelectrophoresis. Rat IgE serum-induced degranulation and histamine release from mast cells were inhibited in a dose dependent fashion by BWD and the inhibition was specific to anti-BWND IgE antibody. BWD may be useful as an hyposensitization agent in buckwheat hypersensitivity, since BWD is a haptenic substance capable of neutralizing specific IgE antibody on mast cells.

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In isolated guinea pig right papillary muscle, the sodium-carrying system (fast inward current) was inactivated by increasing the external potassium concentration from 5.4 to 16 mM (decrease of an equivalent amount of NaCl). The electrical response was recorded with application of relatively strong cathodal current pulses of 10 or 400 msec duration to the muscle across a partition. The results obtained were; (1) the amplitude of the electrical response increased depending on the strength of the stimulation; (2) the mean rate of rise and the overshoot of this response increased markedly with a high concentration of external calcium; (3) the mean rate of rise (Ca²⁺=7.2 mM; 2.01 V/sec) was considerably smaller than that of the action potential; and (4) this electrical response was not affected by tetrodotoxin(4×10^-3M), but was depressed by Mn²⁺ (3×10^-3M). These results suggested that the electrical response (slow response) was due to activation of the slow component of inward current, mainly carried by Ca²⁺. The effect of dobutamine (DOB) on the slow response was studied in vitro, then compared with effects of dopamine (DA), norepinephrine (NE) and isoproterenol (ISO). These catecholamines (CA) increased the amplitude of the slow response and the sensitivity to electrical stimulus strength. Augmentative effects of these drugs were in the following order of ISO>NE>DOB>DA. The finding that DA and ISO increase the sensitivity to electrical stimulus strength more than the amplitude of slow response will be researched in further investigations.

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Effects of adenosine triphosphate (ATP) on the postrotatory-induced nystagmus in rabbits and disorders of vestibular function induced by repeated administration of streptomycin in guinea pigs were studied. ATP-2Na exerted little influence on the postrotatory nystagmus in doses of 3 and 10 mg/kg, i.v., while slight suppressive effects were noted with a dose of 30 mg/kg. On the other hand, diphenidol hydrochloride remarkably suppressed the postrotatory nystagmus in a dose of 3 mg/kg i.v.. The disturbance in vestibular function following administration of streptomycin sulfate (400 mg/kg i.m., once daily×9) was significantly alleviated when concomitant treatment with ATP-2Na (3 mg/kg i.p., 10 mg/kg i.p. and 100 mg/kg p.o., once daily×14)or diphenidol hydrochloride (50 mg/kg p.o., once daily×14) was given. ATP as well as diphenidol alleviated disorders in the vestibular function, while ATP had little influence on vestibular function in intact animals.

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Effects of cinepazide, a vasoactive agent, on regional circulations in various sites of brain and other organs in curarized, artificially respirated cats were studied using a thermoelectrical method. The mechanism of the vascular effect was also investigated. Cinepazide produced a marked increase in blood flow in the cerebellar cortex and an apparent increase in blood flow in the cerebral cortex. Effects of the drug on blood flow in the thalamus, hypothalamus and amygdala were inconsistent. Cinepazide produced the most significant increase in myocardial blood flow and also an apparent increase in muscular blood flow, whereas the drug did not consistently alter hepatic blood flow, and decreased renal and dermal blood flow. Cinepazide produced a mild and sustained fall in blood pressure, however, a transient slight rise in blood pressure was noted when the drug was given into the vertebral artery. It seems possible that the action of cinepazide might involve a mild stimulation of beta adrenergic receptors and slight stimulation of alpha adrenergic receptors but not cholinergic receptors, in the cerebral and peripheral vascular systems. Increase in blood flow induced by cinepazide seems to be mainly due to the smooth muscle relaxant effect and may be mediated via a metabolic mechanism.

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Cardiovascular effects of cinepazide were compared with those of cinnarizine and papaverine. Cinepazide (3-30 mg/kg, i.v.)produced a dose-related and transient increase in vertebral, carotid, renal and femoral arterial flow as well as cardiac output and a decrease in total peripheral resistance in anesthetized dogs. The magnitude and duration of mesenteric vasodilatation induced by cinepazide was much greater as compared to other vascular effects, and these effects were associated with a prolonged hypotension. The drug exerted positive inotropic and chronotropic actions, the latter being followed by bradycardia with the highest dose. Cinnarizine(0.3-3 mg/kg, i.v.)produced a greater increase in vertebral blood flow with bradycardia and papaverine(0.1-1 mg/kg, i.v.)produced a remarkable carotid vasodilatation with cardiac stimulation. Both reference drugs decreased renal blood flow. Cinepazide (30 mg/kg, i.v.)potentiated the vertebral vasodilator response of dogs to intravertebral adenosine and cyclic AMP, while cinnarizine (3 mg/kg i.v.) reduced their vasodilator effects. Intravertebral cinepazide(1-10 mg), like cinnarizine(0.1-1 mg) and papaverine (0.1-1 mg), increased vertebral blood flow in a dose-related manner and the effect was partially inhibited by intravenous pretreatment with aminophylline but not by pretreatment with autonomic antagonists. These antagonists did not modify the cinnarizine effect. Cinepazide resembled cinnarizine and papaverine in that the drug antagonized rabbit aortic contraction induced by KCl, norepinephrine or CaCl₂.

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The β-adrenergic blocking potencies and the antiarrhythmic activities of metabolites of befunolol hydrochloride (BFE-60) were compared with BFE-60 and propranolol. In anesthetized rats and dogs, anti-isoproterenol activities of M I and M II were less potent than BFE-60 but were almost equal to activities of propranolol, while the activity of M III was about 0.1 times as potent as propranolol. M V, M VII, M IX, M I-PG, M I-2G and M II-4G were less effective. In the isolated rat uterus, M II showed an anti-isoproterenol activity that was 0.5 times greater than BFE-60 and propranolol, and the activity of M I was 0.15 times as potent as BFE-60, while those of M III, M V, M VII, M IX, M I-PG, M I-2G and M II-4G were 100 times less potent than BFE-60. Regarding local anesthetic activity using guinea pig cornea, M I showed a similar potency to BFE-60 but M II was 0.2 times as potent as BFE-60. On the l-adrenaline-induced ventricular arrhythmia in anesthetized dogs, M I was as potent as BFE-60, but M II being less potent than BFE-60 was similar to the potency of propranolol. M I also completely prevented the ouabain-induced ventricular arrhythmia in anesthetized dogs in the same manner as BFE-60 and propranolol, while M II was less potent. These results indicate that in β-adrenergic blocking activity, M I and M II have much the same potency as propranolol, and in antiarrhythmic activity, M II is less effective than M I which had a similar potency to propranolol. M III, M V and M VII also had β-adrenergic blocking activities but to a much lesser extent. The other metabolites showed little activity.

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