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Volume 77 (1981)
- Issue 6 Pages 559-
- Issue 5 Pages 447-
- Issue 4 Pages 337-
- Issue 3 Pages 231-
- Issue 2 Pages 99-
- Issue 1 Pages 1-
Volume 77, Issue 3
Displaying 1-8 of 8 articles from this issue
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Masanao HIRAI, Yoshiko MASUBUCHI, Kenji KOMORIYAMA1981 Volume 77 Issue 3 Pages 231-244
Published: 1981
Released on J-STAGE: March 09, 2007
JOURNAL FREE ACCESSAlthough considerable information is available concerning steroidogenesis in the human fetus, the function of the different steroids formed during pregnancy and the factors regulating this delicate hormones balance are poorly understood. During human pregnancy, the placenta synthesizes large quantities of progesterone, estradiol, estrone and estriol and secretes these hormones into both the maternal and fetal circulations; progesterone from maternal lipoprotein-cholesterol, estradiol and estrone from maternal and fetal dehydroepiandrosterone sulfate (DHAS), and estriol largely from fetal 16α-OH-DHAS. It has been demonstrated that preimplantation blastocysts of several animal species have the capacity to accumulate steroids to pregnenolone to progesterone, and to interconvert estrone and estradiol. Estetrol (E4), 15α-hydroxy derivertive of estriol is an interesting compound, since its formation is relatively unique to fetal liver function. Of special interest is that placental sulfatase deficiences result in an extension of the gestation, and Cesarean section has to be done. This raises the question of the role of estrogens in determining the onset of labor, much as in the case of anencephaly. In general, progesterone may decline prior to an abortion, but there has not been a direct application to clinical practice. Estrogen levels during pregnancy are influenced by factors other than fetal well-being and include fetal weight, placental enzyme function, fetal adrenal function, maternal intestinal flora, maternal renal excretion and maternal liver function. Although not yet extensively utilized, such a dynamic test as the infusion of DHAS may yield useful information within a short period in otherwise complicated cases related to fetal and placental function.View full abstractDownload PDF (7357K) -
Yutaka GOMITA, Yasuyuki ICHIMARU, Minehiro MORIYAMA, Kimiko FUKAMACHI, ...1981 Volume 77 Issue 3 Pages 245-259
Published: 1981
Released on J-STAGE: March 09, 2007
JOURNAL FREE ACCESSCoixol (6-methoxybenzoxazolone) contained in Coix Lachryma-Jobi L. var. ma-yuen Stapf was compared with chlorzoxazone with respect to behavioral and EEG effects in mice and rats. Coixol 50 ?? 100 mg/kg, i.p. decreased locomotor activities of both species and produced hypothermia in rats. These effects of coixol were the same in potency as chlorzoxazone given in the same dose. Coixol was approximately twice as potent as chlorzoxazone in potentiating thiopental-induced sleep. This compound attenuated the writhing syndrome induced by 1 % acetic acid and increased the threshold to jumping response induced by foot shock to the same degree as seen with chlorzoxazone. Coixol was equipotent to chlorzoxazone in preventing convulsions induced by maximal electro-shock, while it was about 1.5 times more potent than chlorzoxazone in suppressing pentylenetetrazol-induced convulsion. Coixol 20-100 mg/kg inhibited the lever pressing response of hypothalamic self-stimulation in rats. In rats with chronically implanted electrodes, coixol 50 ?? 100 mg/kg induced drowsy patterns on the spontaneous EEG. The EEG arousal response to the external auditory stimulation was inhibited by the same doses of coixol, whereas it failed to suppress the arousal response to the midbrain reticular stimulation. These results indicate that coixol has pharmacological properties qualitatively similar to chlorzoxazone and acts as a central muscle relaxant with an anti-convulsant effect.View full abstractDownload PDF (6374K) -
Masanao HIRAI, Yoshiko MASUBUCHI, Toshio KUMAI, Akiyo UEMATSU, Kenji K ...1981 Volume 77 Issue 3 Pages 261-272
Published: 1981
Released on J-STAGE: March 09, 2007
JOURNAL FREE ACCESSWe evaluated the dynamics of endogeneous steroid hormones in hypercholesterolemic rats (HLR) F14, F10 in part, obtained by brother-sister mating of Sprague Dawley strain animals. Plasma free and total cholesterol levels in F14 and F10 were significantly high both in both sexes as compared with controls, however, hypertension did not always occur in the HLR; in one group the pressure was elevated but in another, it was normal. Weight of the ovaries was significantly higher than in the controls while weight of the uterus was significantly lower than in the controls. Progestin (progesterone, 20α-OH-P) levels in the ovary were significantly higher (2 ?? 3 times) than in the controls, but the estradiol levels were significantly lower (1/2 ?? 1/3). Cyclic changes in vaginal smears were somewhat irregular and a continuous diestrus was infrequent. Weight of the testicles and the testosterone levels were significantly lower than in the controls while the estradiol level was somewhat higher. Weight of the prostate was normal. In both sexes, adrenal weights were significantly higher than in the controls. In female rats, adrenal corticosterone and 18-OH-DOC were significantly higher than in the controls, but such was not the case in the adrenals of male rats. All our results taken together, suggest that disturbance in hormonal regulation, particularly of the reproductive system in rats occurred in genetically induced hypercholesterolemia.View full abstractDownload PDF (6202K) -
Toshikazu FUKUDA, Keizo ITOH, Takashi NOSE1981 Volume 77 Issue 3 Pages 273-280
Published: 1981
Released on J-STAGE: March 09, 2007
JOURNAL FREE ACCESSEffects of KB-509, a new derivative of benzodiazepines and expected to be classified as an antianxiety drug, were studied on the experimental stress ulcers and serum 11-hydroxycorticosterone (11-OHCS) in mice. Firstly, we looked for a stress procedure under which diazepam would show antiulcerogenic effects at a lower dose than those required for a muscle relaxant effect in this species. We found that diazepam possessed a strong antiulcerogenic activity under the stress procedure (26°C, 5 hr restraint and water immersion). KB-509 had a potent protective effect on the erosions induced by the present mild stress method at a considerably low dose (ED50 : 0.36 mg/kg, p.o.) and the potency was about 3 and 9 times greater than that of diazepam and atropine sulfate, respectively. KB-509 did not affect indomethacin-induced gastric erosions and thermal ulcers, as did diazepam. KB-509 and diazepam depressed stress-induced increase of serum 11-OHCS in mice, but not at the low doses required for antiulcerogenic effects. In conclusion, the results in this study suggest that the stress method described may be used to evaluate the antianxiety effect of benzodiazepines, especially in mice, and that KB-509 is superior to both diazepam and atropine in antiulcerogenic activity.View full abstractDownload PDF (3390K) -
Yasuko KOHNO1981 Volume 77 Issue 3 Pages 281-293
Published: 1981
Released on J-STAGE: March 09, 2007
JOURNAL FREE ACCESSChanges in tryptophan (Trp) concentrations in the peripheral and brain tissues and their influences on brain serotonin (5-HT) metabolism were investigated after i.p. administrations of L-DOPA alone and in combination with Ro4-4602 in male Wistar rats. L-DOPA alone elicited marked increases of both plasma free and liver Trp levels, and a slight increase of brain Trp level. Concomitant application of L-DOPA and Ro4-4602 did not change peripheral Trp concentrations but did reduce brain Trp level. Brain 5-HT levels were reduced in proportion to the increase of dopamine (DA) level by L-DOPA alone and Ro4-4602 plus L-DOPA. A marked increase of 5-HIAA level was exhibited by L-DOPA alone, while Ro4-4602 plus L-DOPA increased 5-HIAA levels slightly despite a marked decrease in 5-HT levels. The decrease of 5-HT and increase of 5-HIAA levels were also observed after administration of L-DOPA to neonatal rats in which the brain tryptophan hydroxylase was considered to be saturated. These results suggest that changes in 5-HT metabolism after L-DOPA injections are not only caused by DA which displaces 5-HT from vesicular stores, but also by changes in Trp concentrations in the plasma and brain which alter 5-HT synthesis and turnover.View full abstractDownload PDF (6514K) -
Yoshito NAKAGAWA, Keisuke TAKEDA, Toyozo HASHIMOTO, Hiroshi SAKURAI, A ...1981 Volume 77 Issue 3 Pages 295-312
Published: 1981
Released on J-STAGE: March 09, 2007
JOURNAL FREE ACCESSEffects of an antihypertensive drug, guanfacine, on blood pressure and heart rate were studied in comparison with findings in a related drug, clonidine. Conscious rats (normotensive rat, SHR, DOCA-hypertensive rat and renal hypertensive rat), anesthetized rats and pithed rats were used. Effects of guanfacine resembled those of clonidine but were about 10 times less potent. Both drugs produced an initial transient increase in blood pressure and a prolonged decrease then followed. In the SHR, a decrease in blood pressure occurred. The vasopressor effect of guanfacine was inhibited by phentolamine (1 mg/kg i.v.) and potentiated after previous treatment of the rats with reserpine (5 mg/kg i.p. 24 hr prior to drug administration, indicating that the effect was produced through activation of peripheral α-adrenoceptors. The vasodepressor effect of guanfacine was clearly dose-dependent, and was more marked when the initial level of the blood pressure was high, while that of clonidine was dose-dependent, only within a limited dosage range. Vasodepressor effects of guanfacine were associated with a decrease in the efferent discharges of the renal sympathetic nerve. Guanfacine, when given intracisternally produced a greater fall of blood pressure and a greater inhibition of the renal nerve activity than when given intravenously. It is concluded that the antihypertensive effects of guanfacine are due to stimulation of α-adrenoceptors within the central nervous system.View full abstractDownload PDF (7488K) -
Susumu OTOMO, Shiro NAKAIKE, Ikuko TSUJI, Chizuko MORI, Masahiro OHZEK ...1981 Volume 77 Issue 3 Pages 313-320
Published: 1981
Released on J-STAGE: March 09, 2007
JOURNAL FREE ACCESSD-penicillamine (D-PA) has beneficial therapeutic effects for patients with rheumatoid arthritis but no convincing explanation has been offered for the mode of action. Experiments reported here were designed to gain an insight into the related mechanisms. Wistar rats were inoculated with various doses of Mycobacterium tuberculosis to induce adjuvant arthritis, and on the 21st day, the lesions of paws and ears were graded according to the extent of the erythema and swelling. Rats given D-PA simultaneously with the inoculation of M. tuberculosis developed a more severe arthritis than that seen in the control group, when they were inoculated with low doses of M. tuberculosis. To investigate the effect of D-PA on hemolytic plaque forming cells (PFC) in the spleen, BDF1 mice were immunized with various doses of sheep red blood cells (SRBC) and D-PA was injected in various doses and at various times. D-PA produced either enhancement or depression of the number of PFC, depending on the dose of antigenic stimulus of SRBC. Furthermore, D-PA slightly enhanced the concanavalin A-induced blastogenesis of the spleen cells in vitro, at a concentration of 1-50 μM, but at concentrations of 500 μM, inhibition was evident. These results indicate that D-PA may act as an immunomodulating agent.View full abstractDownload PDF (3973K) -
Hajime FUJIMURA, Kaito TSURUMI, Tamaki NAKAYAMA, Setsuko KOKUBA, Yasuz ...1981 Volume 77 Issue 3 Pages 321-336
Published: 1981
Released on J-STAGE: March 09, 2007
JOURNAL FREE ACCESSA series of compounds with the general structure of phenylpropionic acid was originally synthesized for antiinflammatory screening. The title compound, TN-762, showed marked anti-inflammatory and analgesic activities and was less toxic. This compound was the same as suprofen which was reported by Janssen to have potent anti-inflammatory and anti-writhing activities. Effects of TN-762 on acute inflammatory reactions and prostaglandin biosynthesis were investigated in animal models and findings compared to those of ketoprofen and indomethacin. TN-762 showed a dose-dependent inhibition at low doses of 5 ?? 20 mg/kg, p.o. on an increased vascular permeability induced by histamine in rats and by acetic acid in mice and carrageenin-induced paw edema in rats. The anti-inflammatory activity of TN-762 was much the same as that of ketoprofen and indomethacin. The inhibitory effect of TN-762 on carrageenin-induced paw edema was not affected by successive administration for 14 days and/or by adrenalectomy. The compound was more active than the two reference compounds in inhibiting ultraviolet erythema in guinea pigs. TN-762 inhibited markedly the arachidonic acid potentiation of carrageenin-induced edema in rat paw, the sudden death following intraveneous administration of arachidonic acid to rabbits and the diarrhea produced by endotoxin in mice, all considered to be induced by biosynthetic prostaglandins. The activities of TN-762 were the same or were more potent than those of ketoprofen and indomethacin. On the contrary, the ulcerogenic activity of TN-762 on the gastrointestinal tract in rats was significantly less than that of ketoprofen and indomethacin. From the above results, TN-762 proved to be a potent inhibitor of acutely-induced inflammation and of prostaglandin biosynthesis, however, the ulcerogenic effects were comparatively diminished.View full abstractDownload PDF (7594K)
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