[The effect of triphenyltin fluoride on aggregation, ATP secretion and malondialdehyde formation of rabbit platelets in vitro]

Recent studies have demonstrated that triphenyltin fluoride (TPTF), widely used as an agricultural chemical and a marine antifoulant, inhibits collagen-induced platelet aggregation and ATP secretion in rabbits ex vivo. The aim of the present investigation was to elucidate the mechanism of the inhibitory action of TPTF by investigating platelet malondialdehyde (MDA) formation, aggregation and ATP secretion following the stimulation by various stimuli of rabbit platelets treated in vitro with TPTF, other triphenyl metals and aspirin. Although no inhibitory effect of TPTF was found on sodium arachidonate-induced platelet aggregation and ATP secretion, TPTF inhibited dose-dependently both platelet aggregation and ATP secretion induced by collagen. The antiaggregating (IC50) concentration of TPTF was 6.0 X 10(-6) M against collagen. In addition, TPTF prevented the collagen-, and thrombin-induced formation of MDA, but had little inhibitory effect on the conversion of exogenous arachidonic acid to MDA in platelets. In contrast, aspirin (10(-3) M) inhibited platelet aggregation, ATP secretion and MDA formation induced by all the stimuli tested. Other triphenyl metals did not any inhibitory effect on collagen-, and sodium arachidonate-induced platelet aggregation and ATP secretion even at a final concentration at 10(-3) M. These results suggest that TPTF has a specific inhibitory effect on platelet aggregation and ATP secretion by acting at some step(s) of platelet membrane between the binding site of collagen and thrombin and the release of arachidonic acid.

[Resistance of mice with active and maternally passive immunity against Sendai virus]

Resistance of mice with active and maternally passive immunity to Sendai virus infection was investigated. Mice with active immunization were convalescent ones from intranasal infection with 10(3) TCID50 of the virus [CT], ones immunized with 4 weekly intranasal injections of about 4 X 10(3) hemagglutinating units (HAU) of formalin-inactivated virus (FV) [IN], or ones immunized with 4 weekly intraperitoneal injections of about 2 X 10(3) HAU of FV [IP]. The serum neutralizing (NT) antibody titers ranged 1 : 10 to 1 : 20 in CT and IN, and 1 : 20 to 1 : 40 in IP at 4 weeks after initial immunization. NT antibody in the lung lavage was detected only in IP in 3/5. After intranasal challenge infection with 10(6) TCID50 of the virus, little or no gross lung lesion, no virus recovery and no body weight loss were observed throughout experiment, in these 3 immunized groups, whereas, control mice showed lung lesions in 4/5 (7 days), virus recovery in 4/5 at 3 days and in 1/5 at 7 days post-challenge, and body weight loss. In additional histological study, bronchiolar epithelial methaplasia and alveolar septal thickening, which were characteristic findings in non-immunized infected mice, were not observed in mice immunized with 2 biweekly injection of about 250 HA of FV and then challenged. Maternal immunity was investigated in offsprings from convalescent dams infected with 10(3) TCID50 at mating [mCT] and from dams immunized intraperitoneally with 4 X 10(3) HAU of FV at 0, 1 and 2 weeks after mating and, 1 and 2 weeks after parturition [mIP]. Serum NT antibody was not detected in mCT, but the titers ranging 1 : 20 to 1 : 40 were detected in mIP. After intranasal challenge of mCT, mIP and offsprings from non-immune mice with 10(3) TCID50 of the virus, virus recovery on day 3 was 2/4, 1/4 and 3/3, and incidence of total lung lesions on day 7 and 12 was 11/21, 2/13 and 16/16, respectively. Body weight gain was suppressed slightly in the immune groups but markedly in the non-immune control.

Body weight changes of mice with different immunity to Sendai virus after challenge infection

Four groups of mice immunized with Sendai virus in different ways, namely convalescent (CT), intrapertoneally (IP) or intranasally (IN) immunized with the inactivated virus and non-immunized (NOI), were challenged and examined degree of immunity and body weight changes. Degree of immunity assessed based on the antibodies, the lung lesions and the lung viral titers was higher in order of CT, IP, IN and NOI. Body weight changes, expressed by both the decrease in mean body weights and the correlation coefficients between pre- and post-challenge, were less in the mice with higher immunity against Sendai virus.

[Properties and mechanism of hyperlipidemia induced in rabbits by tributyltin fluoride]

Male Japanese white rabbits were given tributyltin fluoride (TBTF) by gastric intubation with a single dose of 100 mg/kg body weight and their lipid and glucose metabolisms were investigated. After administration of TBTF, a reversible, but remarkable increase of lipids in plasma, particularly of triglycerides and total cholesterol, was observed. Ultracentrifugation of plasma lipoproteins revealed a marked increase in chylomicron+VLDL (very low density lipoprotein) fraction. Lipoprotein lipase (LPL) activity in postheparin plasma reduced significantly (p less than 0.02) to the levels of about 50% of the control. Fasting blood glucose level was elevated and a significant inhibition of insulin (IRI) release in response to the intravenous glucose infusion was observed in TBTF treated rabbits, but the level of blood glucose and the degree of inhibition of IRI release were low compared with those of triphenyltin fluoride treated rabbits, in which much greater fasting hyperglycemia was observed. Microscopic examination of pancreas, kidneys and thyroid gland did not reveal histological alterations contributing to the hyperlipidemia. These results suggest that hyperlipidemia induced in rabbits by tributyltin fluoride is due to decreased LPL activity. The decrease in LPL activity seems to be related to the inhibition of insulin release from islets by TBTF.

Intestinal uptake site, enterohepatic circulation, and excretion of tetra- and trialkyltin compounds in mammals

The intestinal uptake site, enterohepatic circulation, and excretion into bile, feces, and urine of alkyltins (tetra and trialkyltin) were investigated after oral, sc, or intestinal administration of the compounds to rats and rabbits. Assays of tetra- and trialkyltins in biological materials were carried out by gas chromatography. The main uptake sites in the small intestine were the jejunum and duodenum for tetraalkyltins and the ileum and jejunum for trialkyltins. Tetra- and trialkyltins were detected in the small intestine and contents of the intestinal lumen after sc injection of these compounds in rats. These facts suggest that tetra- and trialkyltins are transported in the body through enterohepatic circulation. The route, rate, and amount of excretion of tetra and trialkyltins seem to depend on the velocity of dealkylation, doses, physical and chemical properties, and route of administration of the compounds.

[Recent progress in the study of analytical methods, toxicity, metabolism and health effects of organotin compounds]

Over the years, a variety of uses has been found of organic tin compounds as fungicides, as stabilizers in plastics and for other industrial uses. The purpose of this article is to summarize and review the results so far obtained as to the analytical method for organotins in biological samples, the toxicity, metabolism, and biochemical and health effects of organotin compounds. 1) Many methods have been developed for analysis of organotin compounds by spectrophotometry, polarography, gas- or liquid-chromatography, etc. These methods, however, are mainly for analysis of organotins in standard solutions or in water, and are not suitable for organotin compounds in biological samples. Recently, we have developed several methods for analysis of various kinds of organotin compounds in biological samples. These methods are able simultaneously to separate and determine trace amounts (at nanogram order) of organotin compounds and their metabolites in the same biological samples. 2) Acute toxicity of organotin compounds which appeared on the literature are summarized. Trialkyl and triaryl compounds seem to be more toxic than the tetra-, di-, or mono-compounds of the same chain length. With an increase in the number of C atoms the toxicity of alkyl compounds decreases. Aryltin compounds are less toxic than alkyltin compounds. 3) Intestinal absorption sites for tetra-alkyltins are jejunum and duodenum, and those for trialkyltins are ileum and jejunum. A considerable amount of orally administered tetra- and trialkyltins of low molecular weights are absorbed, but only very little of the other organotin compounds seems to be absorbed from the gastrointestinal tract. Absorbed organotin compounds rapidly undergo dealkylation by the microsomal mono-oxygenase system dependent on cytochrome P-450 in the liver, brain or other organs, and the compounds and their metabolites distribute to the whole body, ultimately being excreted into urine, bile and faeces. The biological half life of organotin compounds in mammals is usually short, a half of the amount of tributyl- and triphenyl-tins deposited in the body disappearing in several days. A part of organotin compounds excreted into bile is demonstrated to have been absorbed from the intestine and to circulate in the body via enterohepatic circulation. 4) Specific effects of organotin compounds on the biological systems and health include disturbance of the structure and function of the central nervous system (interstitial edema of white matter), inhibited oxidative phosphorylation in mitochondria of cells, atrophy of the thymus and thymus dependent lymphoid tissues resulting in the dysfunction of T cells for immunity, inhibited enzyme activity, lesions in the liver and bile ducts etc., although some specificity is observed among species of animals and organotin compounds. Recently we found that a single oral administration of triphenyltin fluoride to rabbits induces transient diabetes and diabetic lipemia by inhibiting insulin secretion from morphologically normal pancreatic B-cells...

[Elimination of mouse hepatitis virus infection in human malignant tumors transplanted into athymic (nude) mice (author's transl)]

Mouse hepatitis virus (MHV) infection occurred in athymic (nude) mice transplanted with human malignant tumors and 28 out of 38 tumor lines were contaminated with MHV. These 28 tumor lines were passaged in pathogen-free nude mice and 15 of these tumor lines (53.6%) became MHV-free. The MHV infection was eliminated in more than half of the tumor lines by passaging.

Determination of tri-, di-, and monobutyltin and inorganic tin in biological materials and some aspects of their metabolism in rats

A chromatographic method to separate and determine simultaneously trace amounts of tri-, di-, and monobutyltin and inorganic tin (IV) in biological materials has been established. These compounds were eluted stepwise on a silica gel column with an organic solvent system and were sensitively determined by flameless atomic absorption spectrophotometry. The calibration curves show linearity up to 6 mumol/L. The detection limit was 1.5 ng of tin for each of the tin compounds. The reproducibility and recovery were satisfactory. Tetra- and tributyltin were also sensitively determined by the gas chromatographic application of this method. This new method was applied to the study on the metabolism of tributyltin in rats. The contents of tributyltin in the liver of rats, to which a single oral dose of tributyltin fluoride had been administered, showed a rapid decrease following an initial transient increase. The tributyltin, once transported to the liver, seemed to be rapidly dealkylated. The most significant finding was the remarkable retention of monobutyltin and inorganic tin (IV) in the brain.

Simultaneous determination of trialkyltin homologues in biological materials

Taking advantage of the high sensitivity of an electron capture detector to alkyltin halides, an analytical method has been developed for the simultaneous determination of trialkyltin homologues in biological materials. Trialkyltins were purified as chlorides from tissues by simultaneous extraction with hydrochloric acid and ethyl acetate, replacement of the extraction solution with n-hexane and stepwise elution with n-hexane-ethyl acetate on a silica gel column. Alternatively, gas chromatographic analysis was carried out on 20% DEGS-HG at temperatures from 100 to 120 degrees C. Detection limits reached 1 x 10(-12) g for trialkyltin chlorides. The recoveries of trialkyltins added to various tissues at the 50-pmole level ranged from 97 to 106%. By in vivo studies, it was confirmed that this method is rapid, sensitive and applicable to biomaterials containing more than 1 ng trialkyltins per gram of tissue.

Effects of Sendai virus infection on body weight, body temperature and some hematological and serobiochemical values of mice

Body weight and body temperature of JCL: ICR mice infected with Sendai virus decreased depending on the viral dose. In severely infected mice, there were significantly higher values of hemoglobin, hematocrit, red and white blood cell counts, and leucin aminopeptidase (LAP), and lower values of reticulocytes and lactic dehydrogenase (LDH). The other values tested were comparable to those of the non-infected mice.

The effect of age on cadmium retention in organs of hamsters

Age difference of cadmium retention was investigated in hamsters after a short term cadmium exposure. Three types of organs were identified in relation to cadmium retention, i. e., the liver and testes retained an increasing amount of cadmium with increasing age, the kidney and heart showed a gradual decrease in the retention after a transient increase in young ages and the bone showed no retention. These changes seemed to be related to the de novo synthesis of metallothionein in the organ.

Rapid method for the determination of tetraalkyltin compounds in various kinds of biological material by gas chromatography

A rapid gas chromatographic method is described for the simultaneous determination of tetraalkyltin compounds in biological materials. Tetraalkyltins were rapidly purified by direct passage through a silica gel column after extraction from the homogenized tissues with n-hexane. Gas chromatographic analysis was alternatively carried out with PEG 20M at temperatures from 50 to 150 degrees C. A hydrogen flame-ionization detector was more sensitive and selective towards tetraalkyltins than an electron-capture detector. Detection limits reached 1 x 10(-8) g for tetraalkyltins. Recoveries of tetraalkyltins added to various tissues at the 85-nmole level ranged from 97 to 104%. In vivo studies indicated that for a sample containing more than 0.1 micrograms of tetraalkyltins per gram of tissue, the proposed method is accurate enough for quantitative analysis.

Relationship between blood concentrations and clinical effects of a new antidepressant "maprotiline"

In conducting the double-blind controlled study of antidepressants, observations were carried out on the relationship between Maprotiline/Desmethylmaprotiline, concentrations in blood and antidepressive effects, the doses and the incidence of side effects. 1) The maprotiline concentration in the effective group (markedly improved + moderately improved) was 306.9 +/- 112.9 ng/ml, and 244.4 +/- 43.0 ng/ml in the non-effective group (slightly improved + unchanged + aggavated). There was no statistically difference between both groups. 2) Correlations of the maprotiline concentration in blood and together with desmethylmaprotiline to the efficacy (the variation rates in Hamilton's scores) showed a tendency toward higher concentrations in blood with higher therapeutic responses. 3) Side effects were observed in all of the patients with the concentration in blood higher than the mean value (265.2 ng/ml).

Response of athymic nude mice to Sendai virus

Athymic nude mice and euthymic litter mates with BALB/cA back-ground were infected intranasally with a strain of Sendai virus. While no severe illness occurred in euthymic litter mates, some of nude mice showed marked body weight loss and died within 3 weeks after infection. The remaining nude mice recovered from the early depression and survived for 6 weeks or more with chronic pulmonary lesions. The virus was demonstrable in lungs of these chronic cases up to 10 weeks after infection, and none of infected nude mice were found to have anti-Sendai virus antibodies. Pulmonary lesions were characterized by diffuse interstitial pneumonia with a high incidence of prominent adenomatous metaplasia of alveolar epithelium.

East and West

Western psychotherapy is very rationalistic, and especially psychoanalysis regarding the suppression of desire as the cause of neurosis. On the contrary Japanese psychotherapy explains neurosis as the imbalance which is the weak point of human nature. I would like to compare Western and Eastern psychotherapeutic backgrounds.