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Volume 83 (1984)
- Issue 6 Pages 479-
- Issue 5 Pages 373-
- Issue 4 Pages 269-
- Issue 3 Pages 193-
- Issue 2 Pages 93-
- Issue 1 Pages 1-
Volume 83, Issue 3
Displaying 1-8 of 8 articles from this issue
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Kazuya TANIGUCHI1984 Volume 83 Issue 3 Pages 193-206
Published: 1984
Released on J-STAGE: March 07, 2007
JOURNAL FREE ACCESSThe author reviews the molecular properties of Na+, K+-ATPase not only to elucidate the reaction sequence of the enzyme, but also to obtain a better understanding of the mechanism of energy transduction. It is shown that the reaction sequence which had been proposed mainly from phosphorylation kinetics has now been proven by the direct measurment of dynamic fluorescence changes during the hydrolysis of ATP. The formation of MgNaE1 ATP and the transition of NaE1P to E2P accompany the largest fluorescence changes in both the intrinsic and the extrinsic probes, respectively. These findings seem to be a useful step for understanding the mechanism of energy transduction in Na+, K+-ATPase.View full abstractDownload PDF (8145K) -
Takahiro FUTAMI1984 Volume 83 Issue 3 Pages 207-218
Published: 1984
Released on J-STAGE: March 07, 2007
JOURNAL FREE ACCESSStudies were conducted on the actions of counterirritants on muscle contractile mechanisms and nerve conduction in both isolated and intact preparations. Neuromuscular transmission was noncompetitively blocked with menthol and methyl salicylate (MS) and recovered to the control level after they were washed out. Contractions of the isolated frog rectus in response to ACh and electrical stimulation were antagonized with menthol, MS, and camphor; and the action of nonylic vanillyl amide (NVA) became irreversible at high concentration. Menthol and MS produced muscle contraction per se at high concentration and enhanced the caffeine elicited contractile activity. The enhancement was also seen with camphor. The amplitude of the action potential was reduced with menthol, camphor, and MS in a dose and time dependent manner in the isolated frog sciatic nerve. This action was also confirmed in the intraaxonal recordings and was more easily influenced in the small fibres than the large ones. Conduction of primary afferents from muscle and motoneuron was weakly restrained 30 min after the external application of plasters which contained menthol or camphor on the hair-removed skin of cat's hind limb. The refractory period was also apt to be prolonged, and there was an obvious disappearence of group II and III inhibition after the external application of menthol plasters without any effects on group Ia and group Ib inhibition. Concentrations of menthol, camphor, and MS in the muscle that were percutaneously absorbed after the external application of plasters containing these drugs in usual dosage were 10 ?? 30, (ca.) 5, and 5 ?? 10μg/g tissue, respectively. These findings suggest that menthol, camphor, and MS have conductive anesthetic activities mainly being attributable to a suppression of Na+ activation, and they cause an inhibition of nerve conduction, neuromuscular transmission and excitation contraction coupling, and stabilization on the membrane of the ACh receptor. When plasters containing menthol or camphor, in high dose, are externally applied on the skin, weak conductive anesthetic actions are thought to appear which result from the percutaneously absorbed drugs. Counterirritants, in high dose, cause an enhancement on caffeine elicited contraction and muscle contraction per se.View full abstractDownload PDF (5496K) -
Takahiro FUTAMI1984 Volume 83 Issue 3 Pages 219-226
Published: 1984
Released on J-STAGE: March 07, 2007
JOURNAL FREE ACCESSStudies were conducted on the direct actions of counterirritants on the peripheral circulation and the reflex actions on muscular circulation that would refer to skin nerve excitation activated with counterirritants. Blood pressure falling tendencies were observed with menthol, thymol, and methyl salicylate (MS) without any effects on respiration, heart rates, and blood flow in femoral artery and gastrocnemius muscle. Vasodilatation was caused by the direct application of menthol, camphor, and MS in the isolated ear vessels of rabbits, but none of the counterirritants had effects when they were externally applied on the skin of the ear in plaster form. An increase (circa 40%) in gastrocnemius muscle blood flow was induced by the external application of plasters which contained menthol, camphor, or nonylic vanillyl amide (NVA) on the skin of rabbit's hind limb. A slight augmentation was also observed after the application of plasters with MS and without drugs, but these effects disappeared after the hemisection of the dorsal root from Th 13 to S 2. A rise of blood flow in the gastrocnemius muscle elicited by electrical stimulation on the sural nerve of rabbits disappeared almost completely after the pretreatment with propranolol (40 μg/kg, i.v.), but atropine (1 mg/kg, i.v.) had no effect. A rise of blood flow in the deep radial muscle elicited by electrical stimulation on the superficial radial nerve remained after the spinal transection at the C 3 level, and at this time, the Aβ and Aδ components were involved in the superficial radial nerve. These results suggest that when plasters containing counterirritants were externally applied on the skin, direct actions of percutaneously absorbed drugs on peripheral circulation are not expected, but a rise of muscle blood flow is thought to be induced by the spinal somato sympathetic reflex that will cause a suppression on tonic activity in the sympathetic vasoconstrictor nerve or a stimulation on β-adrenoceptors referred to adrenaline released from the adrenal gland.View full abstractDownload PDF (3988K) -
Takahiro FUTAMI1984 Volume 83 Issue 3 Pages 227-235
Published: 1984
Released on J-STAGE: March 07, 2007
JOURNAL FREE ACCESSStudies were conducted on the actions of counterirritants on sensory receptors in the skin and spinal monosynaptic reflex. Nerve discharges in the cat's saphenous nerve were promoted by the external application of menthol and nonylic vanillyl amide (NVA) dissolved in ethanol on the receptive field. When plasters containing counterirritants were externally applied on the receptive field, marked activation was recognized in touch-pressure-pin prick fibers immediately after the application as seen with plaster without drugs, but significantly high activity was maintained thereafter, and the increased firing rate in touch-pressure-pin prick-cold fibers lasted for 60 min. The activity of pressure-pin prick fibers was increased with the lapse of time and warm fibers was not influenced. Effects on activities of spinal dorsal horn cells were almost similar to the changes in activities of primary afferent from the skin. Monosynaptic reflex elicited by stimulation on the medial gastrocnemius nerve was weekly inhibited (significantly different from control at P<0.05), by the external application of plasters, and motoneuron receiving IPSP from the skin lightly touched on was observed. These findings suggest that the receptors activated with counterirritants were thought to be as follows: Aδ and C polymodal nociceptors, AS and C cold nociceptors, and slow adapting cutaneous mechanoreceptors. The cutaneous mechanoreceptors were also activated by the application of plasters. The volley from sensory nerve excited with counterirritants was thought to cause a suppression on the spinal monosynaptic reflex resulting from an inhibition on the motoneuron.View full abstractDownload PDF (4722K) -
Takashi YAJIMA, Tomochika OHNO, Kazuo NAKAMURA, Keiji NAKAMURA1984 Volume 83 Issue 3 Pages 237-248
Published: 1984
Released on J-STAGE: March 07, 2007
JOURNAL FREE ACCESSElectrical stimulation (ES) of the nucleus amygdaloideus centralis (NAmC) and basolateralis (NAmBL), like norepinephrine, decreased mucosal blood flow of the gastric antrum and duodenum and decreased antral motility amplitude in gallamine-immobilized cats. ES of the nucleus lateralis hypothalami (NHL) less extensively produced a similar action. The NAmC stimulation elevated BP and renal sympathetic discharges, whereas the NAmBL stimulation lowered BP. These findings indicate that the gastric and pressor responses to the NAmC stimulation may be attributed to an increase in cerebral sympathetic outflow. Bromazepam dose-dependently (0.1 ?? 1.0 mg/kg, i.v.) prevented these gastric, pressor and renal sympathetic responses to the NAmC stimulation, but it did not alter the depressor response to the NAmBL stimulation or the norepinephrine-induced reactions. Bromazepam less extensively attenuated the gastric and pressor responses to the NHL stimulation. Moreover, bromazepam inhibited stress-induced gastric ulcer formation in rats more markedly than cimetidine, sulpiride and metoclopramide. Bromazepam markedly decreased stress-induced selective increase in the glucose utilization rate in the NAmC among various amygdala nuclei. These results indicate that effects of bromazepam on the gastric and pressor responses to the NAmC stimulation may be due to the inhibition of central sympathetic outflow, and the NAmC are more sensitive to bromazepam than the NHL and other amygdala nuclei.View full abstractDownload PDF (5571K) -
Tsutomu SUZUKI, Toshio YOSHII, Teiko KAWAI, Saizo YANAURA1984 Volume 83 Issue 3 Pages 249-254
Published: 1984
Released on J-STAGE: March 07, 2007
JOURNAL FREE ACCESSWe reported that the reverse tolerance to the effect of morphine on ambulatory activity did not develop in mice treated with morphine-admixed food. In this study, effects of repeated administration of methamphetamine on ambulatory activity were studied in mice treated with morphine-admixed food. The ambulatory activity was determined by the tilting cage method. Methamphetamine injection (1 mg/kg, s.c.) was repeated at 3 ?? 4 day intervals. The ambulatory activity was enhanced progressively when methamphetamine was repeatedly given in mice. However, the enhancing effect was not observed in mice treated with morphine-admixed food (1 mg/g food). Moreover, in a single injection experiment, the effect of the combination of methamphetamine and morphine on ambulatory activity was more potent than that of each drug. These results suggested that the reverse tolerance to methamphetamine did not develop under the condition of exposure to morphine by the DAF (drug-admixed food) method, and the developmental mechanism of reverse tolerance to methamphetamine might be similar to that of morphine.View full abstractDownload PDF (2736K) -
Kiyoko KAJI, Yoshiyuki SEYAMA, Saburo YAMASHITA1984 Volume 83 Issue 3 Pages 255-261
Published: 1984
Released on J-STAGE: March 07, 2007
JOURNAL FREE ACCESSA screening method for the hypolipidemic effect of iodine egg and its active fractions have been investigated with Wistar strain male rats fed on a cholesterol-rich diet. The animals were kept on the cholesterol-rich diet for 5 days, and then iodine egg was fed to them in addition to the above diet for 10 more days. The present method was the most adequate for screening the hypolipidemic effect. Iodine egg yolk was fractionated into the following 3 fractions by Folch's method: Protein (IEY-P), water-soluble (IEY-A) and lipid (IEY-L) fractions. The hypolipidemic effect of these fractions was .determined with the screening method. The marked hypolipidemic effect was induced by the IEY-L fraction. The serum total cholesterol level in rats that received the fraction was 57% as compared with that of the ch group (fed on the cholesterol-rich diet). The other groups showed no such effect. Serum thyroid hormone levels were not affected by the IEY-L fraction which was found to be the active hypolipidemic fraction of iodine egg. The thyroid gland did not seem to participate directly in such a hypolipidemic effect.View full abstractDownload PDF (3110K) -
Shinichi KAWAJIRI, Hiroshi KOJIMA, Akira AKASHI1984 Volume 83 Issue 3 Pages 263-268
Published: 1984
Released on J-STAGE: March 07, 2007
JOURNAL FREE ACCESSMuscle relaxant effects of baclofen were compared with those of dantrolene, diazepam, chlordiazepoxide and tolperisone. When administered intraduodenally (i.d.), baclofen and dantrolene but not diazepam suppressed the sustained rigidity of forelimbs in anemically decerebrated rats, and ED50 values of the former two drugs were 2.9 and 22 mg/kg, respectively. Baclofen, dantrolene and diazepam reduced the phasic rigidity of the decerebrated animals induced by mechanical stimulation of hindlimbs, with their respective ED50 values of 6.2, 140 and 1.4 mg/kg, i.d. Both the rigidities were almost insensitive to chlordiazepoxide and tolperisone. With the exception of tolperisone, these drugs also produced a muscle relaxation in intact animals as measured by traction (rats), rotarod (mice), and grip-strength (mice) tests. ED50 or ED25 values were calculated to be in the following ranges: 5.6 ?? 12 mg/kg, p.o. for baclofen, 15 ?? 35 mg/kg, p.o. for dantrolene, 2.1 ?? 6.5 mg/kg, p.o. for diazepam and 33 ?? 64 mg/kg, p.o. for chlordiazepoxide. These results suggest that baclofen, unlike other drugs, may be effective in reducing both tonic and phasic rigidities at lower doses than those causing muscle relaxation in intact animals.View full abstractDownload PDF (3113K)
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