Search PubMed⌕ Search

Biomedical subjects

S Ueki

Publications and source records attributed to S Ueki.

At least 217 records · Page 12Linked to original sources
PubMed1979

Effect of stimulation of locus coeruleus on the evoked potential in the amygdala in rats.

Effects of stimulation of the locus coeruleus (LC) on evoked potential in the medial amygdala elicited by stimulation of the olfactory bulb (OB-AME potentials) were studied in the gallamine-immobilized rats. The amplitude of the OB-AME potential was inhibited 27.5% by the conditioning stimulation of LC delivered 30 msec before the test stimulation. The inhibitory effect of LC was reduced by propranolol 5 mg/kg i.p., but not by phentolamine 10 mg/kg i.p.. This effect was also reduced by tetrabenazine 10 mg/kg i.p.. Methamphetamine 5 mg/kg i.p. produced considerable potentiation of the LC inhibitory effect and a reduction of the OB-AME potential itself. These results suggest that the LC plays an inhibitory role in the electrical activity of the medial amygdala.

Amygdala↗
PubMed1978

Facilitation of muricide by dorsal norepinephrine bundle lesions in olfactory bulbectomized rats.

The role of the dorsal norepinephrine bundle in the occurrence of muricide was studied in olfactory bulbectomized rats. Although the incidence of muricide was 30% in the olfactory bulbectomized rat, it significantly increased up to 80% and 90% on the 5th and 10th day, respectively, after dorsal bundle lesion. Cortical norepinephrine content decreased by about 50% after dorsal bundle lesions. These results indicate that the dorsal bundle system plays an inhibitory role in the occurrence of muricide in olfactory bulbectomized rats.

Aggression↗
PubMed1978

Synthesis and pharmacological activity of a phosphate ester of delta8-tetrahydrocannabinol.

A water-soluble phosphate ester of delta8-tetrahydrocannabinol (delta8-THC) was synthesized and its pharmacological activities were examined. The cataleptogenic and thiopental sleep-potentiating effects of delta8-THC phosphate in the mouse was approximately 10 and 7% of those of delta8-THC, respectively. However this phosphate showed almost the same potency and a longer duration of hypothermic effect, as compared with delta8-THC in the mouse. The acute toxicity of this phosphate was far lower than that of delta8-THC. delta 8-THC phosphate was difficultly hydrolyzed by alkaline phosphatase or mouse liver homogenate in vitro. The mode of action of the phosphate derivative is discussed in connection with this enzymatically difficult hydrolysis.

Alkaline Phosphatase↗
PubMed1978

[Behavioral and EEG effects of triazolam in comparison with those of diazepam (author's transl)].

Triazolam was 4 to 5 times as potent as diazepam in reducing hyperemotionality of either septal-lesioned or olfactory bulbectomized rats (O.B. rats), and in suppressing muricide in O.B. rats. This agent was equipotent with diazepam in inhibiting fighting behavior of long-term isolated mice, but was longer in duration of action. Triazolam was approximately 4 times more potent than diazepam in preventing pentetrazol convulsion, but was 10 times less potent in inhibiting maximal electroshock convulsion in mice. The muscle relaxant effect of triazolam as assessed by the inclined screen test was 34 times, and the effect on rotarod performance was 17 times more potent than that of diazepam in mice. Triazolam (0.2 approximately 0.5 mg/kg i.v.) changed the EEG to a drowsy pattern in unanesthetized rabbits with a chronic electrode implant, and suppressed the EEG arousal response to auditory stimulation and electrical stimulation given to either the mesencephalic reticular formation or posterior hypothalamus. The limbic afterdischarges induced by either hippocampal or amygdaloid stimulation were also markedly inhibited by triazolam. These EEG effects of triazolam were qualitatively similar to, but were 4 to 5 times more potent than those of diazepam. These results indicate that triazolam is a potent tranquilizer with a longer duration of action, and the muscle relaxant effect is considerable as compared with diazepam.

Aggression↗
PubMed1978

[Effects of triazolam on conditioned behavior in rats (author's transl)].

Effects of triazolam on various types of conditioned behavior were investigated and compared mainly with diaepam in rats. The active conditioned avoidance response of the rat in a Shuttle box was inhibited by triazolam and diazepam only at large doses. The passive avoidance response in a step-down method was not affected by either triazolam or diazepam, but was markedly suppressed by chlorpromazine. The low rate response of hypothalamic self-stimulation behavior was markedly increased by triazolam at doses ranging from 2 to 40 mg/kg p.o., but was suppressed at doses over 80 mg/kg p.o. The high rate response was unaffected by triazolam even at doses of 40 approximately 180 mg/kg p.o. The low rate response was increased by diazepam at doses of 1 approximately 10 mg/kg p.o. and was suppressed at 80 mg/kg p.o. The high rate response was reduced by diazepam at 180 mg/kg p.o. In the conflict situation of the rat subjected to food reward and foot-shock punishment, the lever press response in the unpunished period was reduced by triazolam at doses of 1 approximately 5 mg/kg p.o., whereas that in the punished period was markedly increased. Similar effects were observed with diazepam at doses of 15 approximately 20 mg/kg p.o. Triazolam appeared to be 10 approximately 15 times more potent than diazepam in this anticonfluct effect. Thus, triazolam appears to be a potent antianxiety agent.

Animals↗
PubMed1978

[Psychopharmacological effects of flutazolam (MS-4101) (author's transl)].

Behavioral effects of Flutazolam (MS-4101), a new derivative of benzodiazepines, was investigated and compared with effects of diazepam in mice and rats. MS-4101 suppressed hyperemotionality in septal rats, fighting behavior in long-term isolated mice and pentylenetetrazol convulsion and potentiated thiopental sleep. These effects of MS-4101 were the same in potency as those of diazepam. MS-4101 was more potent than diazepam in reducing the spontaneous locomotor activity in the open-field test and potentiating the stimulant effect of methamphetamine on locomotor activity. On the other hand, suppression of hyperemotionality in O. B. rats, potentiation of ethanol-induced anesthesia, prevention of maximal electroshock, prevention of strychnine convulsin and muscle relaxant effect of MS-4101 were less potent than in the case of diazepam. MS-4101 had also an anticonflict effect, which was less potent than that seen with diazepam. Suppression of locomotor activity was potentiated by chronic administration of MS-4101, but disappeared with chronic administration of diazepam. MS-4101 inhibited considerably both scratching and head-twitch induced by mescaline in mice. Scratching was increased with small doses of diazepam and decreased with high doses. Head-twitch was decreased with small doses of diazepam and increased with high doses.

Agonistic Behavior↗