The Japanese Journal of Pharmacology
Online ISSN : 1347-3506
Print ISSN : 0021-5198
ISSN-L : 0021-5198
Volume 56, Issue 4
Displaying 1-23 of 23 articles from this issue
  • Seiji Ichida, Syunji Ariyoshi, Takashi Fujisue, Tetsuyuki Wada, Takafu ...
    1991 Volume 56 Issue 4 Pages 397-402
    Published: 1991
    Released on J-STAGE: July 11, 2006
    JOURNAL FREE ACCESS
    The characteristics of the stimulating effects of the calcium channel agonists BAY K 8644, CGP28392 and YC-170 on 45Ca uptake by rat uterine segments were investigated. BAY K 8644, CGP28392 and YC-170 caused about 150, 100 and 150% increase, respectively in the 45Ca uptake induced by 20 mM KCl. The ED50 values of BAY K 8644, CGP28392 and YC-170 were 1.8 × 10-9, 2.5 × 10-8 and 9.8 × 10-9 M, respectively. These agonists had little effect on the 45Ca uptake induced by 10-6 M acetylcholine. They also did not affect the basal 45Ca uptake. Their enhancing effects were blocked by the Ca channel antagonist nitrendipine. We conclude that rat uterine segments have voltage-sensitive Ca channels that are stimulated by Ca channel agonists (BAY K 8644, CGP28392 and YC-170) under depolarizing conditions and that the characteristics of the stimulating effects of CGP28392 and YC-170 on 45Ca uptake by rat uterine segments are qualitatively the same as those of BAY K 8644.
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  • Taeko Hata, Atsufumi Kawabata, Eiji Itoh
    1991 Volume 56 Issue 4 Pages 403-412
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    Blood coagulation and fibrinolytic activity was studied in SART (specific alternation of rhythm in temperature)-stressed animals found to exhibit thrombocytopenia and prolonged bleeding time, and drug effects on the abnormalities were evaluated. 1) SART-stressed rats revealed prolongation of activated partial thromboplastin and thrombin time, no change in prothrombin time, decreased plasma fibrinogen levels, and shortened euglobulin clot lvsis time (ELT). Antithrombin III and α2-plasmin inhibitor activity remained constant following stress exposure. 2) During stress, fibrinogen levels declined from day 5 and remained depressed up to day 14. Reduction in ELT developed in a similar manner to fibrinogen. 3) Decreased fibrinogen levels were prevented by consecutive doses of tranexamic acid, an antifibrinolytic, and Neurotropin, a sedative analgesic. Shortened ELT was counteracted by chronic treatment with Neurotropin and alprazolam, an anxiolytic. Single administrations of the above agents failed to affect either change. These results indicate that SART-stressed animals exhibit suppressed intrinsic coagulability and enhanced fibrinolytic activity, but normal extrinsic coagulability. Considering the previous report together with the above results, the hemostatic system under SART stress tends uniformly toward hemorrhage. Moreover, Neurotropin appears to improve and normalize hemostatic imbalance due to SART stress, a chronic form of stress.
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  • Michiko Saito, Shigefumi Serikyaku, Ryoichi Ishitani
    1991 Volume 56 Issue 4 Pages 413-419
    Published: 1991
    Released on J-STAGE: July 11, 2006
    JOURNAL FREE ACCESS
    To investigate a link between membrane phospholipids and tryptamine binding molecules, we examined the effects of phospholipases A2 and D on the temperature-sensitive high-affinity [3H]tryptamine binding sites in rat brain. When the phospholipase A2-treated membranes were exposed to 1% bovine serum albumin (BSA) before assaying for [3H]tryptamine binding, a complete dose-dependent inhibition curve was observed. At a concentration of 0.03 U, the action of phospholipase A2 resulted in the splitting of phosphatidylserine (PS), choline phosphatides (PC) and ethanolamine phosphatides (PE) by about 32, 34 and 65%, respectively, and reduced [3H]ligand binding by about 32%. On the contrary, in the case of phospholipase D (500 U), PS and PC decreased by about 8% and 33% and PE by about 29% with no significant alteration in the binding capacity. Moreover, Scatchard analysis of the [3H]tryptamine binding showed that phospholipase A2 drastically increased only the KD value of the high affinity sites, and this was accompanied by a decrement of the Bmax values of both the high and low affinity binding sites. From these results, it is inferred that certain lipids (PS) may be a modulator for the function of the temperature-induced high-affinity [3H]tryptamine binding molecules.
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  • Akio Fujimura, Kyo-ichi Ohashi, Akio Ebihara
    1991 Volume 56 Issue 4 Pages 421-426
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    The present study was undertaken to examine whether the urinary amount of furosemide is influenced by chronic lithium treatment. LiCl at 2 mEq/kg/day in 1 ml vehicle (5% glucose solution) or 1 ml of vehicle alone was injected intraperitoneally for 8 days into Wistar rats. On day 8, 30 mg/kg of furosemide in 3% body weight of 1 % NaCl was given orally, and urine was collected for 6 hr after dosage. The urinary amount of furosemide in the Li-treated rats was significantly lower than that in the control animals [Li group (n = 12): 514 ± 75 (mean ± S.E.) vs. control group (n = 12): 916 ± 85 μg/kg/6 hr, P < 0.01]. This finding indicates that pharmacokinetic alterations of furosemide might occur during chronic treatment with lithium.
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  • Shin-ichi Morishita, Masamichi Shoji, Yasuhiro Oguni, Chihiro Ito, Kat ...
    1991 Volume 56 Issue 4 Pages 427-432
    Published: 1991
    Released on J-STAGE: July 11, 2006
    JOURNAL FREE ACCESS
    A low-output-type heart failure model was established in rabbits by protease treatment of the surface of the left ventricular anterior wall. Heart rate, aortic blood flow (AoF), left ventricular pressure (LVP) and maximal rate of rise of LVP (max dP/dt) in this model were maintained at lower levels than in normal rabbits, while left ventricular end-diastolic pressure (LVEDP) and systemic vascular resistance (SVR) were maintained at higher levels, and mean blood pressure (MBP) remained at a normal level. Intraduodenal administration of digoxin and a drug containing toad venom (Kyushin®: KY) improved the hemodynamic parameters by increasing the AoF, LVP and max dP/dt and by decreasing the LVEDP and SVR without a significant change in MBP. These results suggest that the beneficial effects of digoxin and KY on this heart failure model originate from their cardiotonic activity.
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  • Hideki Takase, Osamu Inoue, Yuji Saito, Eizaburou Yumioka, Akira Suzuk ...
    1991 Volume 56 Issue 4 Pages 433-439
    Published: 1991
    Released on J-STAGE: July 11, 2006
    JOURNAL FREE ACCESS
    We investigated the involvement of sulfhydryl compounds in the cytoprotective effect of each component herb drug composing Oren-gedoku-to (OGT) against ethanol-induced gastric lesions and potential difference (PD) reduction in comparison with that of OGT in rats. Pretreatment with N-ethylmaleimide (NEM) significantly blocked the cytoprotective effects of OGT, Coptidis rhizoma and Phellodendri cortex, but did not block the cytoprotective effects of Gardeniae fructus and Scutellariae radix. The inhibitory effects of OGT, Coptidis rhizoma and Phellodendri cortex against the PD reduction disappeared in the presence of NEM or diethyldithiocarbamate (DDC), whereas NEM or DDC had little or no effect with Gardeniae fructus and Scutellariae radix. These results suggest that the gastric mucosal protection of Coptidis rhizoma and Phellodendri cortex may be ascribed to the reinforcement of mucosal barrier resistance through endogenous sulfhydryl compounds and DDC-sensitive compounds, but those of Gardeniae fructus and Scutellariae radix may be independent of NEM or DDC-sensitive compounds.
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  • Yoichi Yoshida, Hiroshi Mori, Kanji Inami, Akihide Koda
    1991 Volume 56 Issue 4 Pages 441-455
    Published: 1991
    Released on J-STAGE: July 11, 2006
    JOURNAL FREE ACCESS
    Previously, we purified a substance from swine prostate extract (PE) that had been reported to have therapeutic effect on benign prostatic hypertrophy. The purified substance (PPE) suppressed 3H-testosterone uptake into the prostate in castrated rats. The present study was carried out to examine the effect of PPE on the weight of accessory sexual organs including the prostate and biochemical parameters in the prostate of normal and/or castrated and testosterone-treated rats. 1) In normal rats, the p.o. administration of PPE daily for a total of 30 days did not affect the prostate weight, but reduced the citric acid content in the prostate. The treatment had little or no influence tissue O2 uptake, aconitase activity or isocitrate dehydrogenase activity in the prostate. 2) In castrated and testosterone-treated rats, the p.o. treatment with PPE for 15 or 30 days reduced the weight of the prostate as well as the total citric acid, DNA and RNA contents in prostatic tissue. However, these biochemical parameters per tissue weight were not obviously affected except for the citric acid content. These findings suggest that PPE is one of the active principals of PE for the therapeutic efficiency on benign prostatic hypertrophy, probably due to its suppressive effect on excessive uptake of androgen by the prostate.
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  • Hisashi Kuribara, Toshio Asashi, Sakutaro Tadokoro
    1991 Volume 56 Issue 4 Pages 457-463
    Published: 1991
    Released on J-STAGE: July 11, 2006
    JOURNAL FREE ACCESS
    The interaction between oploid analgesics (morphine and buprenorphine) and central depressants (ethanol, pentobarbital and diazepam) was investigated by means of ambulatory activity in mice. The ambulation-increasing effect of both morphine (10 mg/kg, s.c.) and buprenorphine (1 mg/kg, s.c.) was enhanced by the combined administration of ethanol (0.8-3.2 g/kg, p.o.) in a dose-dependent manner. Naloxone (0.1 mg/kg, s.c.) was effective for reducing the enhanced ambulatory activity. The pretreatment with Ca-cyanamide (5 mg/kg, p.o., 30 min before) reduced the enhancement of the ambulation-increasing effect induced by the combined administration of opioid analgesics with ethanol, although it scarcely modified that of morphine and buprenorphine alone. On the other hand, neither pentobarbital (1-30 mg/kg, s.c.) nor diazepam (0.25-2 mg/kg, s.c.) modified markedly the ambulation-increasing effect of morphine and buprenorphine. The present results suggest that ethanol specifically interacted with opioid analgesics when the mouse's ambulatory activity was used as the indicator.
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  • Tomohisa Hattori, Mikio Ito, Yoshio Suzuki
    1991 Volume 56 Issue 4 Pages 465-473
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    The effect of TJ-8014, a lyophilized extract of Syo-Saiko-To without Zingiberis rhizoma, annexing Coptidis rhizoma and Hoelen, on puromycin aminonucleoside (PAN) nephrosis in comparison with the effect of dipyridamole was evaluated. PAN nephrosis was induced in rats by intraperitoneal injections of PAN, once daily for 6 days. When TJ-8014 was given from the initial day of PAN treatment (just before PAN injection) at 2.0 g and 4.0 g/kg/day, p.o., it was markedly inhibited urinary protein excretion and elevation of serum cholesterol content throughout the experimental periods. In addition, the mild adhesion of Bowman's capsule to capillary walls in glomeruli was also improved by TJ-8014 at 2.0 g and 4.0 g/kg/day, p.o. Dipyridamole was also effective in inhibiting the urinary protein excretion as well as his topathological changes. TJ-8014 at 4.0 g/kg/day, p.o. inhibited the decrease in super-oxide dismutase (SOD-like), catalase and glutathione peroxidase activities in the renal cortex and SOD-like activity in the glomeruli in PAN-induced nephrosis. Dipyridamole failed to inhibit the decrease in scavenger activities. These results suggest that TJ-8014 is effective against PAN-induced nephrosis, and they suggest that the mechanisms of action of this medicine may be partly due to the enhancing activities of scavengers in the renal cortex and glomeruli.
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  • Masayuki Uchida, Shingo Yano, Kazuo Watanabe
    1991 Volume 56 Issue 4 Pages 475-481
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    In order to establish a reliable method for the production of gastric astral ulcer in rats, combined treatments with three factors: a vagal stimulant, a mucosal barrier breaker and a necrotizing agent were investigated. By the combined administration of 2-deoxy-D-glucose (2-DG; 200 mg/kg, i.v.), aspirin (100-400 mg/kg, p.o.) and hydrochloric acid (0.15 and 0.35N, 0.5-1.5 ml/100 g, p.o.) or ammonia solution (0.5-1.0%, 0.5-1.5 ml/100 g, p.o.), gastric lesions were prominently induced in sites of both the corpus and antrum on day 2. The largest antral ulcer was induced by the combination of 2-DG (200 mg/kg), aspirin (200 mg/kg) and ammonia solution (1%, 10 ml/kg); and the mean antral ulcer index (mm2) was 43.1 ± 4.4 and the incidence was 100%. The antral ulcer was found to penetrate the muscularis mucosae and still observed on day 21 and day 28 after ulcer induction in a few cases. From these findings, it was indicated that this antral ulcer would be a useful model for studying the etiology and therapy of gastric ulcer disease.
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  • Kenichi Furusawa
    1991 Volume 56 Issue 4 Pages 483-493
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    A new task for the analysis of drug effects on the cognitive function in mice was investigated using a 4-arm maze with three selectable arms. Each trial consisted of a forced run either to the right or left arm containing a food pellet, which was changed for each trial, followed by a free-choice run after a delay (0-120 sec). The correct response was to turn to the arm 180 degrees opposite from the forced one. Entrance into the center arm in the free-choice run, which was called the non-reward response, was not reinforced at any time. As the delay became longer, correct responses decreased, but non-reward response errors remained unchanged in the well-trained mice. Without increasing the non-reward response, scopolamine and atropine, but not methylscopolamine, decreased the correct response in a delay-dependent manner at a low dose range, while diazepam did so in a delay-independent manner. Physostigmine ameliorated scopolamine-induced impairment in performance, but had less effect on the delay-induced decrease in the correct response. Other tested drugs (chlorpromazine, haloperidol, apomorphine, phentolamine, propranolol, lithium chloride, ketamine, and caffeine) had no significant effect on performance. These results suggest that CNS muscarinic blockades and diazepam treatment selectively attenuate working memory in different ways.
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  • Hiroshi Hisajima, Takehiko Miyagawa, Hiroshi Saito, Nobuyoshi Nishiyam ...
    1991 Volume 56 Issue 4 Pages 495-503
    Published: 1991
    Released on J-STAGE: July 11, 2006
    JOURNAL FREE ACCESS
    Neurotrophic activities of human recombinant acidic fibroblast growth factor (haFGF) were evaluated on primary cultured neurons from various brain regions and compared with those of CS23, modified human basic fibroblast growth factor. Survival of cultured neurons from embryonic day 16 (E16) rat cortex and substantia nigra was significantly increased by the addition of more than 10 ng/ml haFGF and that from the hippocampus was increased by 100 and 1000 ng/ml. However, enhancement of viability by haFGF was observed only in 1000 ng/ml-treated neurons from the striatum, thalamus, colliculus and cerebellum; and it was not observed in septal neurons. Survival of cultured neurons from postnatal day 15 rat on glial feeder layer was significantly increased by the addition of 1000 ng/ml haFGF, except for neurons from the septum. CS23 (10 ng/ml) increased the survival of cultured neurons from all regions mentioned above, and its effects were stronger than those of 1000 ng/ml haFGF. Addition of more than 10 ng/ml haFGF significantly increased the survival of cultured neurons from neonatal day 2 rat retina. Addition of 1000 ng/ml haFGF increased the choline acetyl transferase activity of E16 septal neurons slightly but significantly, but didn't increase the dopamine uptake activity of embryonic day E15 ventral midbrain. These results show that haFGF is effective on limited regions and ages of brain and retina, while CS23 is effective on all regions tested.
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  • Koichi Ebii, Reiko Fukunaga, Takashi Taniguchi, Motohatsu Fujiwara, Su ...
    1991 Volume 56 Issue 4 Pages 505-512
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    We studied the effects of chronic administration of β-adrenoceptor antagonists with and without intrinsic sympathomimetic activity (ISA): carteolol (with ISA) and propranolol (without ISA), respectively, on the heart of spontaneously hypertensive rat (SHR) and Wistar Kyoto rat (WKY). Six-week-old SHRs and WKYs were orally given carteolol or propranolol for ten weeks. The heart rate was reduced in propranolol-treated SHR, but not in carteolol-treated ones. In WKY, carteolol-treatment increased the heart rate. The number and affinities of β-adrenoceptors were analyzed using [3H]dihydroalprenolol as a ligand. Propranolol at 30 mg/kg increased the number of cardiac β-adrenoceptors in both SHR and WKY. In contrast, 10 mg/kg carteolol significantly decreased the number of cardiac β-adrenoceptors in SHR, but not in WKY. These data indicate that carteolol, a β-adrenoceptor antagonist with ISA, does not cause up-regulation of the number of cardiac β-adrenoceptors in the rat and suggest that this fact is related to a possible lack of “rebound phenomena” after sudden discontinuation of chronic carteolol-therapy in humans.
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  • Makoto Kawamura, Satoshi Yamazaki, Akihiro Tobe, Shin-ichiro Watanabe, ...
    1991 Volume 56 Issue 4 Pages 513-522
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    In the present study, we investigated the effects of MCI-727, a new anti-ulcer agent, on plasma immunoreactive secretin concentration in rats and dogs using secretin specific RIA with the ethanol extraction method. Plasma secretin levels were increased dose-dependently 10 min after oral administration of MCI-727 in rats (control: 5.5 ± 0.6; MCI-727, 10 mg/kg: 10.4 ± 2.6; 30 mg/kg: 15.3 ± 1.5; 100 mg/kg: 20.7 ± 2.6 pg/ml, n = 6). Teprenone also caused a significant increase of plasma secretin at 10 min after oral administration at the doses of 30, 100 and 300 mg/kg. Under the same conditions, MCI-727 and teprenone did not alter the plasma immunoreactive gastrin concentration in rats. From the results of the time course study, the increasing effect of MCI-727 (30 mg/kg, p.o.) on plasma secretin remained for at least 240 min after administration. On the other hand, the increasing effect of teprenone (200 mg/kg, p.o.) was only observed at 30 and 60 min after administration. Furthermore, MCI-727 had increasing effects on plasma secretin concentration in dogs, but teprenone had no effects in this species. The volume of pancreatic secretion and the pancreatic bicarbonate output increased after intra-duodenal administration of MCI-727 at 30 and 100 mg/kg in rats. Similar effects were also observed with teprenone (30-300 mg/kg, i.d.) or secretin (Secrepan®, 0.1-1.0 unit/kg, i.v.).
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  • Hiroshi Tsuchihashi, Keiko Maruyama, Shoko Baba, Fumie Mano, Junji Kin ...
    1991 Volume 56 Issue 4 Pages 523-530
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    Scatchard analyses of 3H-prazosin binding in rat brain membranes showed biphasic curves, which identified the presence of α1High- and α1Low-affinity sites. The α1High-affinity site was completely inhibited by 0.1 μM phenoxybenzamine. On the other hand, 3H-prazosin binding in rat spleen membranes resulted in linear curves that were identical to the binding curve for the α1High-affinity site in the brain. The displacement potencies of α1-adrenergic antagonists were characterized by 3H-prazosin binding to α1High-affinity sites in the rat spleen and brain and α1Low-affinity sites in the brain in the presence of 0.1 μM of phenoxybenzamine. The affinities of WB-4101, phenoxybenzamine, phentolamine, chlorpromazine, labetalol and nifedipine for brain α1High-affinity sites were significantly higher than those in the spleen. The affinities of most ligands for α1Low-affinity sites were significantly lower than those for both α1High-affinity sites in the brain and spleen, but chlorethylclonidine was significantly selective for α1Low-affinity sites, and bunazosin, dibenamine and 5HT had the same affinities for the α1Low- and both α1High-affinity sites. These results show that two α1-adrenoceptor subtypes, α1High- and α1Low-affinity, are present in the rat brain and that a different α1High-subtype, exists in the rat spleen.
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  • Francis Hombhanje
    1991 Volume 56 Issue 4 Pages 531-534
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    The effect of different doses of sulphadimidine (250, 500, 750 and 1000 mg) on acetylation capacity in 10 normal individuals was investigated in a randomized cross-over study design. The subjects were initially phenotyped with an oral dose of 750 mg of sulphadimidine. Four weeks later, each subject was assigned four different doses of sulphadimidine. The acetylator phenotype was classified for each dose as rapid if the percentage of acetylated sulphadimidine in the post-dose 5-6 hour urine is more than 70% and as slow if less than 70%. The results indicate a clear separation into two phenotypes, even with the smallest dose of the drug. A slow acetylator in the 10 subjects showed a saturation of the acetylation capacity with increasing doses. This trend was not observed in the remaining subjects who were identified as rapid acetylators regardless of the doses. An oral dose of 750 mg of sulphadimidine is suggested as a ‘standard’ or optimum dose for acetylator phenotype testing.
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  • Yoshinobu Takata, Junko Ozawa, Hitoshi Kato
    1991 Volume 56 Issue 4 Pages 535-538
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    The low Ca2+ + tetraethylammonium (TEA) medium enhanced electrically evoked norepinephrine release by 3.5-fold in canine saphenous veins. ω-Conotoxin GVIA (ω-CTX) inhibited the neurotransmission more markedly in low Ca2+ + TEA medium than in normal Krebs medium. This is the case for the inhibition by tetrodotoxin, though to a lesser extent. The inhibition by ω-CTX was competitively antagonized by elevating external Ca2+ The results indicate that low Ca2+ + TEA medium is useful for studying the effect of Ca antagonists on adrenergic neurotransmission, because ω-CTX acts more effectively in this medium.
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  • Mitsuhiro Nagata, Yoshitsugu Osumi
    1991 Volume 56 Issue 4 Pages 539-542
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    Roles of nicotinic receptors in the dorsal motor nucleus of the vagus (DMV) in the regulation of gastric motility were investigated in urethane-anesthetized rats in which an intragastric balloon had been placed. Nicotine (0.1 nmole) microinjected into the DMV but not the nucleus ambiguus induced dual changes, a decrease followed by an increase in gastric motility. Administration of 0.1 nmole of hexamethonium into the DMV significantly inhibited the decrease in gastric motility induced by intravenously administered nicotine.
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  • Masahiro Kawamura, Takashi Matsui, Akiyoshi Niitsu, Tsutomu Kondo, Yuj ...
    1991 Volume 56 Issue 4 Pages 543-545
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    Effects of ATP and other purine derivatives on steroidogenesis in primary cultured bovine adrenocortical fasciculata cells were examined. At concentrations higher than 1 μM, ATP showed a potent stimulative effect on the cortisol production of the cells. The potency order of the steroidogenic effect of the tested purine derivatives was ATP > ADP >> adenosine >> AMP. α, β-Methylene ATP had no stimulative effect on the steroidogenesis at concentrations as high as 1 mM. Theophylline did not antagonize the steroidogenic effect of ATP. These results suggest that bovine adrenocortical fasciculata cells possess the P2y purinoceptors that are linked to steroidogenesis.
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  • Shoji Takakura, Teruo Susumu, Hisashi Satoh, Jo Mori, Akihiko Shiino, ...
    1991 Volume 56 Issue 4 Pages 547-550
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    The effects of nilvadipine, a dihydropyridine type calcium channel blocker, on cerebral infarction induced by focal brain ischemia was studied in rats. The area of infarction was measured 24 hr after occlusion of the middle cerebral artery (MCA) in spontaneously hypertensive rats using triphenyltetrazolium chloride. Nilvadipine, given immediately after MCA occlusion, reduced the area of infarction significantly at doses of 0.32 mg/kg (i.p.) and 3.2, 10 and 32 mg/kg (p.o.). Nicardipine suppressed the area of infarction at a dose of 32 mg/kg (p.o.). The results suggest that nilvadipine is effective against ischemic brain injury.
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  • Hiromichi Nakamuta, Yoshihiko Itokazu, Masao Koida, Ronald C. Orlowski ...
    1991 Volume 56 Issue 4 Pages 551-555
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    Using 125I-salmon calcitonin (sCT) as a ligand, in vitro autoradiography of rat brain outlined specific anatomical localization of human calcitonin (hCT) sensitive binding sites. The results presented herein show that there are hCT sensitive binding sites in the ventral part of the lateral septum among the sCT specific binding sites distributed throughout the diencephalon.
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  • Junzo Kamei, Hiroaki Tanihara, Yutaka Kasuya
    1991 Volume 56 Issue 4 Pages 557-561
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    We examined whether the chronic administration of selective κ-opioid agonists could produce antitussive tolerance, in a comparison with the μ-opioid morphine. A certain degree of tolerance to the antitussive effects of morphine appeared in rats treated chronically with this drug. However, chronic administration of U-50, 488H and U-62, 066E, highly selective agonists for the κ-opioid receptor, does not result in the development of tolerance to their respective antitussive effects. These results suggest that the ability of κ-opioid agonists to cause tolerance to their respective antitussive effects was lower than that of a μ-opioid agonist.
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  • Kazuho Abe, Yuka Iri, Megumi Takayanagi, Hiroshi Saito
    1991 Volume 56 Issue 4 Pages 563-566
    Published: 1991
    Released on J-STAGE: July 11, 2006
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    The influences of K-252a and staurosporine, protein kinase inhibitors, on neurotrophic effects of basic fibroblast growth factor (bFGF) were investigated in dissociated cell cultures of the striatum, hippocampus and cerebellum of fetal rats. Addition of 1 ng/ml bFGF enhanced the survival of cultured neurons of all brain regions tested. Both K-252a (10-200 nM) and staurosporine (1-100 nM) blocked the survival promoting effects of bFGF in a concentration-dependent manner. These results suggest that bFGF exerts its neurotrophic effects through activation of protein kinase(s).
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