Yoshitsugu Osumi

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Twenty-four right-handed, right hemiparetic patients with Broca's aphasia were examined for their singing capacity. Twenty-one (87.5%) produced good melogy. Twelve of these (57%) produced good text words while singing. It is speculated that the right hemisphere is dominant over the left for singing capacity. The relationship between melodic and text singing(More)
The effects of neurotensin on the release of endogenous dopamine (DA) from rat striatal slices were investigated. DA was extracted by the aluminium adsorption method and assayed electrochemically by high-performance liquid chromatography. Neurotensin (2-100 microM) potentiated the potassium-induced release of striatal endogenous DA in a(More)
The correlation between acid secretion and mucosal blood flow in the rat stomach during stress loading was determined to provide clues to the etiology of the gastric ulceration which thus occurs. The gastric acid output was increased remarkably by water-immersion stress at 23 degrees C, and this increase lasted while the stress was given, yet the mucosal(More)
The effects of nicotine microinjected into several brain regions on the centrally elevated gastric acid output and mucosal blood flow (MBF) were examined in anesthetized rats. Intravenous administration of 2-deoxy-D-glucose (2-DG) induced increases in gastric acid output and MBF. These increases were inhibited dose dependently by nicotine microinjected into(More)
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(More)
We examined the properties of voltage-gated calcium channels mediating endogenous dopamine (DA) and acetylcholine (ACh) release in the isolated rat retina. Application of 30 mM KCl elicited the release of DA and ACh, and these releases were abolished in Ca(2+)-free medium. The high K(+)-evoked DA release was largely blocked by both of omega-agatoxin IVA and(More)
Intracerebroventricular (i.c.v.) administration of bombesin (0.1, 1.0, 10.0 nmol/animal) in urethane-anesthetized rats induced long-lasting and dose dependent increases in plasma levels of adrenaline and noradrenaline. These effects of bombesin were inhibited by i.c.v. pretreatment with indomethacin (50-500 micrograms/animal), while the same dose of(More)
Intracerebroventricularly (i.c.v.) administered nicotine 50 and 100 nmol produced dual changes, an early decrease and a successive increase in gastric motility in urethane-anesthetized rats in which an intragastric balloon had been placed. These dual effects of nicotine were significantly antagonized by simultaneously administered hexamethonium i.c.v. but(More)
We applied a microdialysis technique for the measurement of hypothalamic thromboxane B2, a stable metabolite of thromboxane A2, in urethane-anesthetized rats. Perfusion with N-methyl-D-aspartate (1.5 and 2.5mM) of the paraventricular nucleus by microdialysis probe concentration-dependently elevated the levels of thromboxane B2 in this region and plasma(More)
The nociceptive reflex activity and analgesic effect of morphine were studied in rats using the hind paw stimulation test. The stimulation threshold was significantly increased in animals with bilateral destruction of the locus coeruleus (LC), and was reduced after lesion of the dorsal raphe nucleus (DR). LC lesions produced a selective lowering of(More)