Biomedical subjects

Mitsuhiro Furuse

Publications and source records attributed to Mitsuhiro Furuse.

41 records · Page 3Linked to original sources

PubMed2003

Beta 3-adrenergic receptor is involved in feeding regulation in chicks.

We examined whether the brain beta 3-adrenergic receptor (B3-AR) is involved in the feeding regulation of chicks. Intracerebroventricular (ICV) injection of BRL37344, a B3-AR agonist, reduced food intake of chicks under ad libitum, but not fasting, feeding conditions. The ICV injection of BRL37344 did not affect chick posture or locomotion activity suggesting that BRL37344 inhibited feeding without induction of sleep-like behavior as caused by norepinephrine. Furthermore, the rectal temperature increased following the ICV injection of BRL37344. Intraperitoneal administration of BRL37344 did not reduce food intake under ad libitum feeding condition. The present study demonstrated that the brain B3-AR is involved in the inhibition of feeding in chicks. We also suggested that activation of the brain affects the energy metabolism in chicks.

Adrenergic alpha-Agonists↗

PubMed2003

Effect of acute L-tryptophan exposure on the brain serotonergic system and behavior in the male medaka.

The aim of this study was to investigate the effect of exposure to L-tryptophan (TRP) on the metabolism of 5-hydroxytryptamine (5HT) and behavior of medaka. In the first experiment, the fish were exposed to a 0, 1, 2 or 4 g/l of TRP solution for 24 hr. Although no significant difference in the brain 5HT content was detected, 5-hydroxyindoleacetic acid (5HIAA), a major 5HT metabolite, increased in a dose-dependent fashion. In the second experiment, the fish were maintained in a 0 or 4 g/l of TRP solution for 28 hr, and then their behaviors were monitored. The fish reared in under TRP solution were divided into two groups and transferred to either fresh water or a TRP solution. The locomotion of the TRP-treated group significantly increased compared to the control group irrespective of water conditions. It was suggested that TRP exposure activated the brain 5HTnergic systems and stimulated behavior of medaka.

Animals↗

PubMed2003

Changes in catecholamines and dopaminergic metabolites in pigeon brain during development from the late embryonic stage toward hatch.

While brain development during embryogenesis has been extensively studied in precocial birds, there is no information available on altricial birds. Thus, the concentrations of the catecholamines norepinephrine (NE), epinephrine (E), and dopamine (DA), and the dopaminergic metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and 4-hydroxy-3-methoxyphenylacetic acid (HVA) were determined at several stages during the late embryonic period (E13, E14, E15, E16, E17 and E18) and the day-of-hatch (P0) in the pigeon telencephalon, cerebellum, optic lobe, and brainstem. The concentrations of all catecholamines were higher than those reported in chicken embryos. During embryogenesis, NE, E, DOPAC and HVA concentrations in the various brain parts increased throughout embryonic development until shortly before hatching at which time they decreased. DA, however, continued to increase through hatching in the brainstem, and the changes in DA concentrations varied in several brain parts. In conclusion, catecholamine concentrations in the various brain parts tended to increase with embryonic age, and the concentrations were higher than those in chickens. Furthermore, brain catcholamine metabolism changed at hatch in pigeons.

Animals↗

PubMed2002

Chicken ghrelin and growth hormone-releasing peptide-2 inhibit food intake of neonatal chicks.

Ghrelin is an endogenous ligand for the growth hormone secretagogue (GHS) receptor. Ghrelin stimulates feeding in rats, however, intracerebroventricular (i.c.v.) injection of rat ghrelin inhibits feeding of neonatal chicks. In the present study, the effect of i.c.v. injection of different ghrelins including chicken and bullfrog ghrelin, and synthetic GH-releasing peptide (GHRP) on feeding of neonatal chicks was investigated. Chicken ghrelin strongly suppressed feeding. To compare the inhibitory effect, chicken and rat ghrelin were examined. The suppressive effect of feeding by chicken and rat ghrelin was almost identical. Bullfrog ghrelin contains a change in the acylated amino acid from Ser to Thr, strongly suppressed feeding. The i.c.v. injection of GHRP-2 (KP-102), a synthetic GHS, also inhibited feeding. These results indicate that the chicken GHS receptor is affected by several forms of GHS, and that food intake of neonatal chicks is inhibited by GHS receptor agonists.

Animals↗

PubMed2002

Intracerebroventricular administration of octopamine stimulates food intake of chicks through alpha(2)-adrenoceptor.

Octopamine, known to be an important neurotransmitter in invertebrates, has been noted to have several similarities to noradrenaline (NA) in mammals. The present study was done to elucidate whether central injection of octopamine enhances the feeding behavior of chicks and to investigate the interaction of octopamine with both alpha(1)- and alpha(2)-adrenoceptors. We found that the intracerebroventricular injection of octopamine significantly stimulated food intake of neonatal chicks during 30 min postinjection, but not thereafter. Moreover, this octopamine-induced eating response was attenuated by the alpha(2)-antagonist yohimbine, but not by the alpha(1)-antagonist prazosin. These results suggest that the action of octopamine on the feeding behavior of the neonatal chick is similar to that of NA, since octopamine regulates food intake through the alpha(2)-adrenoceptor.

Adrenergic alpha-2 Receptor Agonists↗