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Volume 89 (1987)
- Issue 6 Pages 317-
- Issue 5 Pages 243-
- Issue 4 Pages 169-
- Issue 3 Pages 103-
- Issue 2 Pages 55-
- Issue 1 Pages 1-
Volume 89, Issue 4
Displaying 1-9 of 9 articles from this issue
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Atsushi SONE1987 Volume 89 Issue 4 Pages 169-173
Published: 1987
Released on J-STAGE: February 23, 2007
JOURNAL FREE ACCESSFerulic acid (FA) specifically inhibits the growth of the ventral prostate in rats not through antiandrogenic mechanisms (Saito et al. Experientia 35: 696, 1979). Levels of polyamines in the rat ventral prostate were determined before and after FA administration (10, 25 and 50 mg/kg BW, s.c., for 5 days). SD strain male rats, 5 ?? 7 weeks of age, were used. The ventral prostates were homogenized with 10% TCA and centrifuged. The supernatant was washed twice with diethylether, freeze-dried, and redissolved in distilled water. Then, the contents of putrescine, spermidine and spermine were measured by an isotachograph (LKB), using a leading buffer composed of 5 mM Ba (OH)2/15 mM valine, pH 9.94, and a terminating buffer composed of 20 mM triethylenediamine, pH 10.20. Total polyamines were reduced dose-dependently (12.12, 9.95, 9.10 and 7.74 nmol/mg wet tissue at 0, 10, 25 and 50 mg/kg FA, respectively). Spermidine was more sensitive to FA than spermine. According to the attitude of the Spermidine/Spermine ratio, the inhibition of ornithine decarboxylase by FA has been suggested.View full abstractDownload PDF (3545K) -
Noriko TANIGAKI, Kenji MANNO, Kunio SUGIHARA, Naomasa MIKI, Seiji ICHI ...1987 Volume 89 Issue 4 Pages 175-180
Published: 1987
Released on J-STAGE: February 23, 2007
JOURNAL FREE ACCESSEffect of a novel antidepressant, paroxetine, on the uptake of serotonin (5-HT), noradrenaline (NA) and dopamine (DA) as well as on various neuro-receptors were investigated in comparison with those of the tricyclic antidepressants amitriptyline, chlorimipramine and imipramine. Paroxetine showed a potent 5-HT uptake inhibitory action, giving the NA/5-HT ratio of 886 in comparison with the ratios of 1.7, 15 and 1.5 for amitriptyline, chlorimipramine and imipramine, respectively. On the other hand, paroxetine showed almost no inhibitory action on the binding of the [3H]-labeled ligands examined in this study ([3H]quinuclidinyl benzilate, [3H]5-HT, [3H]ketanserine, [3H]pyrilamine, [3H]dihydroalprenolol, [3H]prazosin, [3H]clonidine and [3H]spiroperidol). In contrast, the tricyclic antidepressants showed inhibitory action on a number of bindings and also revealed comparatively high affinities especially for muscarine, histamine-1 and αl-adrenaline receptors responsible for the side effects. From the above findings, it can be concluded that paroxetine has only a weak affinity for various neuro-receptors and inhibits specifically 5-HT uptake.View full abstractDownload PDF (5293K) -
Yuko KUGA1987 Volume 89 Issue 4 Pages 181-190
Published: 1987
Released on J-STAGE: February 23, 2007
JOURNAL FREE ACCESSThe effect of l-thyroxine administration from 2 to 10 days of age (Neo-T4) on the behavioral development was studied. Serum T4 levels in Neo-T4 rats showed a marked and dose-related decrease at 15 days of age and a less marked decrease at 62 days of age. The locomotor activity of the Neo-T4 rats was higher at 13 ?? 19 days of age and tended to be lower at 62 days of age than in the controls. At 17 days of age, apomorphine (0.1 mg/kg, s.c.) induced a marked increase in the frequency of sniffing down in the control males, whereas a decrease was noted in the Neo-T4 males. Age-matched females in both groups responded to apomorphine with a slight decrease in sniffing down behavior. An increase in the frequency of sniffing down by apomorphine (0.5 mg/kg) in adult Neo-T4 rats was less marked. TRH administration failed to induce hyperthermia in adult Neo-T4 males. The results indicate that neonatal administration of T4 in the rat induces alterations in the functional development of the brain in varying degrees dependent upon the functional integration of the neurons. An involvement of sex hormones is suggested.View full abstractDownload PDF (7766K) -
Hiromichi NAKAMUTA, Masao KOIDA, Yasunao OGAWA, Ronald C. Orlowski1987 Volume 89 Issue 4 Pages 191-195
Published: 1987
Released on J-STAGE: February 23, 2007
JOURNAL FREE ACCESSIt has been reported based on animal studies that salmon calcitonin (sCT), besides hypocalcemic action, exhibits a variety of pharmacological actions. The anorectic action has been observed to ensue not only by central administration but also by peripheral injection, indicating that in clinical use to induce hypocalcemia or for other therapeutic purposes, the anorectic action may develop as a side effect. While studying the anorectic effect of [Gly8]-sCT in rats, a derivative of sCT having rather stronger hypocalcemic potency than the mother molecule, it was found that on peripheral injection, the derivative practically lacks the anorectic effect. Thus, a pharmacological evaluation of the novel peptide was made. 1) When injected subcutaneously in rats at a dose level of 1 U/kg, sCT and the derivative induced similar patterns of hypocalcemia in either of which hypocalcemia reached a peak between 1 and 3 hr after injection. No notable difference existed between the action of the two peptides. 2) In rats which were trained to take the daily food need within 2 hr (17:00 ?? 19:00), an intracerebroventricular injection of 1 U/rat of either peptide 30 min before food presentation significantly reduced both food and water intake, causing a loss of body weight as compared with the control which received the injection of saline alone. By subcutaneous injection of 100 U/kg, sCT was also active to decrease food and water intake. The effect was found to last longer than 24 hr and to cause a marked loss in body weight. In contrast, such effects did not develop in rats treated with the derivative. 3) Both peptides were able to suppress the specific binding of 125I-sCT to the membrane fraction of rat brain and kidney. The IC50s of sCT estimated for brain and kidney were 0.71 and 1.2 nM, respectively, and those of the derivative were 3.1 and 3.2 nM, respectively. 4) A subcutaneous injection of either peptide in a dose level of 50 U/kg caused a rise by 45% in blood sugar. The results obtained herein show that the peripheral anorectic effect of sCT differ in the action mechanism from that of the central one and would be a biochemically independent action from the hypocalcemic or hyperglycemic action, and the effect is lost on replacement of the Val-residue at the 8th position by a Gly-residue, suggesting that [G1y8]-sCT may be clinically a better substitute for sCT with less side effect.View full abstractDownload PDF (4148K) -
Osamu IRINO, Kiyoshi SAITOH, Kazuyoshi BANDO, Masayuki UCHIDA, Hideo H ...1987 Volume 89 Issue 4 Pages 197-202
Published: 1987
Released on J-STAGE: February 23, 2007
JOURNAL FREE ACCESSEffects of ifenprodil tartrate on whole blood filtrability ex vivo in rats was investigated by a standard technique for measuring whole blood filtration time passed through a filter (5 μm). Ifenprodil tartrate was observed to reduce the filtration time dose-responsively. This effect was especially evident at 20 mg/kg (P<0.05). On the other hand, no effect on the hematocrit value, plasma concentration of fibrinogen, erythrocyte count or mean cellular volume of erythrocytes was observed. These results indicated the increasing effects ex vivo of ifenprodil tartrate on erythrocyte deformability. The ex vivo effects on erythrocyte deformability was manifested without changing the ATP contents, ATP/ADP ratio or adenylate energy charge in erythrocytes; and a phenothiazine-like amelioration in the shape of crenated erythrocytes was observed. These results suggested that the effect of ifenprodil tartrate on erythrocyte deformability ex vivo might be due to direct action on the erythrocyte membrane. At 0.3 mg/kg, i.v., ifenprodil tartrate significantly (P<0.05) increased the blood flow in the hypothalamus of conscious rats. Thus, it was indicated that ifenprodil tartrate, which increases the erythrocyte deformability and the cerebral blood flow, is useful for the therapeutic treatment of cerebrovascular accidents.View full abstractDownload PDF (5452K) -
Kanjiro YASUDA1987 Volume 89 Issue 4 Pages 203-211
Published: 1987
Released on J-STAGE: February 23, 2007
JOURNAL FREE ACCESSFunctional development of the brain of rats exposed to methylazoxymethanol (MAM) at a dose of 1, 5 or 20 mg/kg, i.p., on day 15 of fetal life was assessed using pharmacological responses to several CNS acting drugs. In the rats treated with 20 mg/kg of MAM, the following results were observed: A marked decrease in the rearing activity in an openfield, failure of the development of supersensitivity in cataleptic response to haloperidol administered weekly, an increase in the head down sniffing frequency after apomorphine administration, prolongation of pentobarbital-induced sleeping time, a decrease in the seizure threshold to picrotoxin and kainic acid, and a significant decrease in the growth rate. In addition, the rats administered 1 mg/kg of MAM, which have been reported to detect no biochemical changes in the brain, exhibited different responses to the drugs used: A marked decrease in the rearing activity, nearly normal threshold to picrotoxin and kainic acid, a pronounced hypothermia after chlorpromazine administration, and no significant change in the brain weights. The results suggest that rats exposed to MAM in varying doses would be useful for evaluating the developmental process of neurons and its unification.View full abstractDownload PDF (6829K) -
Kiyoshi KURIYAMA, Yoshiyuki HIYAMA, Kiyoshi ITO, Kiyonoshin ICHIKAWA, ...1987 Volume 89 Issue 4 Pages 213-224
Published: 1987
Released on J-STAGE: February 23, 2007
JOURNAL FREE ACCESSThe pharmacological properties of KP-136 were studied using cutaneous reactions in rats and guinea pigs. KP-136 remarkably inhibited the passive cutaneous anaphylaxis (PCA) with intravenous and oral dosing. However, the inhibitory effect of KP-136 had an apparent species difference. Thus, KP-136 was more effective on rat PCA than that of guinea pig. In four rat cutaneous reactions produced by three allergic reactions and compound 48/80, KP-136 was remarkably effective on two homologous PCA induced by IgE and IgGa. The intravenous and oral doses for 50% inhibition on the PCA were 0.2 mg/kg to 0.4 mg/kg and 0.5 mg/kg to 0.9 mg/kg, respectively. KP-136 was scarcely effective on cutaneous reactions elicited by intradermal injection of histamine and serotonin which are main chemical mediators in rat homologous PCA. However, KP-136 blocked the degranulation of mast cells and decrease of histamine content in skin elicited by. the PCA. In addition, KP-l36 showed a potent inhibition on the immunological release of histamine from rat peritoneal exudate cells. The concentration for 50% inhibition on the histamine release was 5 ng/ml. These findings indicate that KP-136 is an oral potent inhibitor on PCA, and it acts by blocking the release of chemical mediator (s) from mast cells.View full abstractDownload PDF (8644K) -
Satoshi YUKI, Mitsuo HANAZUKA, Toshiaki WATANABE, Hiroyoshi NISHI1987 Volume 89 Issue 4 Pages 225-233
Published: 1987
Released on J-STAGE: February 23, 2007
JOURNAL FREE ACCESSThe hypotensive activity of terazosin has been attributed to inhibition of postsynaptic alpha-1 adrenoceptors. The present study examined the influence of terazosin on spontaneous sympathetic outflow in anesthetize and immobilized rats. The effects on blood pressure and heart rate were also evaluated. Intravenously (i.v.) injected terazosin 0.3 mg/kg and prazosin 0.1 mg/kg increased a sympathetic outflow by 15.4 and 21.6%, respectively. These drugs produced a significant and long-lasting fall in blood pressure with slight heart rate change. On the contrary, clonidine 0.1 mg/kg, i.v. significantly inhibited the sympathetic outflow by 69.2%. The in trace re broventricularly administered 10μg/kg clonidine also showed the sympathoinhibitory effect. However 3μg/kg, i.c.v. of terazosin and prazosin increased the sympathetic tone by 16 and 7.2%. During these periods, the both drugs slightly decreased the blood pressure. These changes in hemodynamic parameters and nerve activities were obtained at 2 ?? 3 min after the i.c.v. administration. The 10 μg/kg, i.c.v. of terazosin and prazosin significantly inhibited the pressor response by phenylephrine 1 μg/kg, i.v. These results indicate the peripheral effect of terazosin and prazosin through the penetration of the drugs from the brain. The results provide evidence that terazosin, like prazosin, dose not affect cardiovascular regulation by a central action.View full abstractDownload PDF (6222K) -
Kenichi USAMI, Atsufumi MANABE, Sadao NAKAYAMA, Koji SAKAMOTO1987 Volume 89 Issue 4 Pages 235-241
Published: 1987
Released on J-STAGE: February 23, 2007
JOURNAL FREE ACCESSThe effects of phenol, guaiacol and m-cresol on erythrocytes, hepatocytes, dipalmitoyl phosphatidylcholine (DPPC)-liposomes and surface tension were studied at various concentrations. Phenol at 10 mM caused a slight inhibition of hypotonic hemolysis in rat erythrocytes. Guaiacol at 4 and 10 mM and m-cresol at 0.6 to 10 mM caused a significant inhibition of hypotonic hemolysis. In the enzyme leakage from isolated rat hepatocytes, phenol at 0.001 to 0.4 mM and 2 to 10 mM, guaiacol at 2 to 10 mM and m-cresol at 0.001 to 4 mM caused an inhibition in GOT leakage. The leakage of GPT from hepatocytes was inhibited by phenol at 0.4 to 10 mM, guaiacol at 2 to 10 mM, and m-cresol at 0.001 to 4 mM. m-Cresol at 10 mM caused increases in GOT and GPT leakage. The inhibition of phenol and m-cresol on the LDH leakage in hepatocytes were observed at a concentration of 0.001 mM and 0.1 to 1 mM and 1 mM, respectively. Guaiacol or m-cresol at 10 mM caused an increase in LDH leakage. Phase-transition temperature of DPPC-liposomes was depressed by phenol and m-cresol at 1 to 10 mM and by guaiacol at 5 and 10 mM. Guaiacol at 1 and 10 mM and m-cresol at 10 mM caused a depression of surface tension, but phenol caused no change in surface tension. The order of effects on erythrocyte, hepatocyte and DPPC-liposome membranes was m-cresol>phenol≥guaiacol. In the present study, phenol and its related compound showed a positive correlation between their effects on various membranes and germicidal effects as evaluated by the phenol coefficient, but the effects were not related to a depression of surface tension.View full abstractDownload PDF (5453K)
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