Takayuki Tani

The vasodilator action of formaldehyde in dogs.

The perfused hind legs of anesthetized dogs were used in investigations of the depressor effect of formaldehyde. An injection of formaldehyde into the right femoral vein caused a transient fall in systemic blood pressure and a one-step fall in perfusion pressure. The initial fall took place before the arrival of the drug in the perfused area. It was followed by a further decrease after the arrival of the drug in the area. Our study showed that dogs completely lack the pressor response to formaldehyde that rats have been reported to manifest. Though the initial fall in perfusion pressure was little affected by atropine or vagotomy, it was abolished by autonomic ganglion blocker, adrenergic neuron blocker, and a-adrenergic blocker. These results suggest that the initial decrease is caused by inhibition of the sympathetic nervous system. This in turn suggests that the depressor action of formaldehyde results from a combination of direct action on the cardiovascular system and inhibitory action on the sympathetic nervous system. The inhibition plays a smaller role in the depressor action than the vasodilator effect, because a-blockers in intact dogs augmented, rather than inhibited, the depressor effect.

Effects of free fatty acids on the binding of steroid hormones to bovine serum albumin

The effects of binding of free fatty acids (FFA) to bovine serum albumin (BSA) on steroid hormone binding to BSA were examined. The FFA studied included myristic, palmitic, stearic, oleic and linoleic acids. The binding coefficient K was estimated from the changes in the equilibrium partition coefficient between the aqueous and the hexane phase caused by the addition to BSA to the aqueous phase. A noticeable effect of FFA binding (molar ratio FFA/BSA, 2∶1) on the affinities of α-estradiol, ethynylestradiol and dehydroisoandrosterone to BSA was not observed: however, the affinities of progesterone, androsterone and testosterone were distinctly enhanced by FFA binding. Furthermore, the elution profiles of gel filtration chromatography clearly showed that progesterone and testosterone are easily liberated from the hormone/BSA complexes and that stronger binding of these hormones to BSA is caused by binding of FFA to BSA. The affinity of ethynylestradiol to BSA is stronger than that of progesterone and testosterone and is not affected by palmitic acid binding to BSA.

Transport of steroid hormones facilitated by serum proteins

The affinities with steroid hormones (alpha-estradiol, ethynylestradiol, progesterone, androsterone, dehydroisoandrosterone and testosterone) were observed for Cohns fraction IV-1 and V (albumin). It was estimated from the comparison with the binding coefficient K (protein-bound form/free form of hormone) in a 3.5% (w/v) bovine serum albumin (BSA) solution that 40-80% of bound hormone in bovine serum is the BSA-bound form. It becomes clear in a liquid membrane system consisting of a hexane source phase (I), a water phase and a hexane receiving phase (II) that the transport flux of hormone is governed primarily by the partition coefficients between the water/hexane phases. In the case of a hormone with a lower partition coefficient, the uptake process from the hexane phase (I) to the water phase is a rate-determining step in the transport system and the serum proteins accelerate the transport of hormones, while with an increase in the partition coefficient the rate-determining step changes from the uptake step to the release step from the water phase to the hexane phase (II) and the hormone transport is decelerated owing to the significant decrease of free hormone concentration in the aqueous phase by the associated with serum proteins for the system having the restricted amount of hormone in the hexane source phase.

Chemiluminescence detection of organotin compounds with bis(2,4,6-trichlorophenyl) oxalate by flow-injection analysis

Abstract The chemiluminescence (CL) reaction of bis(2,4,6-trichlorophenyl) oxalate with hydrogen peroxide was applied to the detection of fluorescent organotin-quinoline complexes using a flow-injection system. Four organotin compounds, i.e., di- n -butylin dichloride (DBTC), diphenyltin dichloride (DPTC), tri- n -butylin chloride (TBTC) and triphenyltin chloride (TPTC), were examined in conjunction with 2-methyl-8-hydroxyquinoline. Factors affecting the CL intensity such as solvents, reagent concentrations, pH and flow-rate were studied. The detection limits for DBTC, DPTC, TBTC and TPTC were 0.5 μM (3 ng), 1.25 μM (8.6 ng), 25 μM (162.7 ng) and 100 μM (770.9 ng), respectively, with a signal-to-noise ratio of 3.

Hygienic Chemistry of Cyanide in Waste Water

It has been discussed and proposed by the Central Pharmaceutical Affairs Council of Japan that the maximum allowable concentration of cyanide ion (CN-) in plating waste water should be under 2 ppm. The standard value of 2 ppm is not applied to such complex cyanides as ferrocyanide and ferricyanide, but to the free cyanide which is liberated by aeration through the test solution at pH 5.0 and 50∼55°C, because the toxicity of the complex cyanide is less than onethousandth of that of the free cyanide. The determination procedure of free cyanide ion listed in Japanese Industrial Standard (JISK0102-1964) was modified to improve in several points, for example, pH control of the test solution and the adoption of ball filter in aeration apparatus and 1N NaOH solution as absorbing solution for HCN. The methods for removal of HCN, such as alkali-chlorine method and Fe-complex method, were reviewed shortly.