(1) Outline of research subjects
(2) Staff and Aspect of the laboratory
(3) Recent publication list
Although
several subjects of researches are proceeding in our laboratory, especially following
two topics recently have been focused. At the first, I would like to introduce
the outline of those research subjects, and then introduce our laboratory.
(1)
Outline of research subjects
The first research subject is 「fundamental
study on biological rhythm in rats and chick」. The reason for usage of rats
and chick is that circadian oscillator is localized in suprachiasmatic nucleus
and pineal gland, respectively. Recently many clock-related genes have been discovered,
and the regulatory mechanism ticking about 24 hour has been clarified. We recently
discovered new peptide regulating circadian oscillator by collaboration with
Dr. Kojima (Molecular Genetics, Institute of Life Science, Kurume
University). This
peptide consists of 23 amino acid, which was first purified from porcine spinal
cord in 1985 and named neuromedine U (NMU). Actually, we found that NMU
immuno-reactive cells and NMU specific receptors are abundant in
suprachiasmatic nucleus. In addition, NMU knockout mouse erased the circadian
locomotor activity rhythms. Intracerebroventricular injection of NMU caused
phase-dependent phase shift of circadian rhythm in rats. So, NMU is expected as
a new peptide regulating circadian oscillator. In avian species, we previously
reported that individual pineal cell possesses photoreceptor, circadian oscillator
and melatonin synthetic capacity. However, how clock produce the melatonin
rhythm has been puzzle for a long time. We recently clarified the cascade for
cellular signaling pathway between circadian oscillator and melatonin
synthesis.
The second research subject is 「fundamental
and applied study on novel appetite stimulating hormone, ghrelin, and
inhibitory hormone NMU」, which has been supported by Nestle Science Promotion Committee. This subject has been begun
since last four years, by collaboration with Dr. Nakazato (Third
Department of Internal Medicine, Miyazaki Medical College ). Ghrelin was
isolated as an endogenous ligand for GH secretagogue receptor, but we found
that ghrelin has a strong appetite stimulating action. Our laboratory has unique
research technique, such as punch out of specific nucleus from frozen brain
slice within few minutes; this is applied to PCR and so on. In addition, in our
laboratory, we used many field techniques including brain surgery,
electrophysiology, endocrinology, reproduction, cell and tissue culture,
immuno-histochemistry, RIA of several hormones, gene cloning, gene targeting
animals and so on. These techniques are useful to search physiological
functions of novel peptide. Using these techniques, we found that ghrelin plays
important roles on fetal development, milk secretion, gastric acid secretion, and
cell proliferation. On the other hand, we found that NMU also plays important role
for reflection, stress, and biological rhythms.
(2) Aspect of the
laboratory
Two staffs (Professor and assistant professor), 2 postdoctoral
researchers , 2 technical officers, 2 doctor course students (1 foreign student
from Egypt), 10 undergraduate students are belong in our laboratory in 2004.
All students have to present their results or introduce some journal papers
during our weekly laboratory meeting. As all students have a turn doing
quickly, they have to work hard to prepare the experimental results for their
next presentation. Actually, almost of them don’t have weekend holiday. In our
veterinary course, there is no master course, because 6 years are required to
graduate. Therefore, graduate thesis is very important credit courses. We actively
encourage all students to present their experimental data at many academic conferences.
Undergraduate students are obligated to present their research at any
conferences once at least during undergraduate. They are looking forward to eat
local dishes at place where a meeting is held. We also conduct undergraduate
students to submit the manuscript to international journal. Sometimes some student
writes two or three papers until graduation. Our laboratory have may parties as
annual events, such as reception for new students in spring, camping in summer,
Christmas party in winter, farewell party and so on.
Professor: Noboru Murakami
Assistant Professor: Keiko Nakahara
(3) Publication
list
2004
K. Nakahara, R. Hanada, N.
Murakami, H. Teranishi, H. Ohgusu, N. Fukushima, M. Moriyama, T. Ida, K.
Kangawa, M. Kojima
The gut-brain peptide neuromedin
U is involved in the mammalian circadian oscillator system
Biochemical
and Biophysical Research Communications 318:156-161,2004
K.Nakahara, Y.
Egi, M.Kojima, R. Hanada, T.Ida, M. Miyazato, K.Kangawa, N.Murakami
Neuromedin U is
involved in nociceptive reflexes and adaptation to environmental stimuli in
mice
Biochemical and Biophysical Research Communications 323:615-620, 2004
R Hanada, H Teranishi, J T
Pearson, M Kurokawa, H Hosoda, N Fukushima, Y Fukue, R Serino, H Fujihara, Y
Ueta, M Ikawa, M Okabe, N Murakami, M Shirai, H Yoshimatsu, K Kangawa, M Kojima
Neuromedin U has a novel
anorexigenic effect independent of the leptin-signaling pathway
Nature Medicine 10:1067-1073, 2004
M. Yokoyama, K.
Nakahara, M. Kojima, H. Hosoda, K. Kangawa, N. Murakami
Ghrelin in dogs:
distribution, role, and response to feeding
European Journal
of Endocrinology in press
S Shousha, K Nakahara, M Miyazato, K Kangawa, N Murakami
Endogenous
neuromedin U has anorectic effects in the Japanese quail
General and Comparative
Endocrinology in press
K Nakahara, K Fukui and N
Murakami
Involvement of thalamic
paraventricular nucleus in the anticipatory locomotor activity under food
restriction in the rat
J.Vet.Med. Sci. 66:1297-1300,2004
2003
Toshinai K, Date Y, Murakami
N, Shimada M, Guan J, Wang Q, Funahashi H, Sakurai T, Shioda S, Matsukura S,
Kangawa K, Nakazato M.:
Ghrelin-induced food intake
is mediated via the orexin pathway.
Endocrinology 144(4):1506-1512,2003;
Shimada M, Date Y, Mondal MS,
Toshinai K, Shimbara T, Fukunaga K, Murakami N, Miyazato M, Kangawa K,
Yoshimatsu H, Matsuo H, Nakazato M.:
Somatostatin suppresses
ghrelin secretion from the rat stomach.
Biochem Biophys Res Commun, 302(3):520-5,2003
Mondal MS, Date Y, Murakami N, Toshinai
K, Shimbara T, Kangawa K, Nakazato M.
Neuromedin U
Acts in the Central Nervous System to Inhibit Gastric Acid Secretion via
Corticotropin-Releasing Hormone System
Am J Physiol Gastrointest Liver Physiol. 284(6):G963-G969、2003
K Nakahara, T
Hayashida, M Nakazato, M Kojima, H Hosoda, K Kangawa, N Murakami
Effect of
Chronic Treatments with Ghrelin on Milk Secretion in Lactating Rats
Biochem
Biophys Res Commun 303(3):751-755,
2003
K
Nakahara, T Kawano, K Shiota and N Murakami
Effects of microinjection of melatonin into various brain regions
of Japanese quail on the locomotor activity and body temperature
Neuroscience Letter in press 2003
T Hanada,
Y Date, T Shimbara, S Sakihara, N Murakami, Y Hayashi, Y Kanai, T Suda, K Kangawa,
M Nakazato
Central actions of neuromedin
U via corticotropin-releasing hormone.
Biochem Biophys Res Commun. 2003 Nov 28;311(4):954-8.
2002
K. Nakahara, Y. Abe, T. Murakami, K. Shiota and N. Murakami
Pituitary adenylate
cyclase-activating polypeptide (PACAP) is involved in melatonin release via the
specific receptor PACAP-r1, but not in the circadian oscillator, in chick
pineal cells
Brain Research 939:19-25,2002
T Hayashida, K Nakahara, M, S. Mondal, M Nakazato, M,
Kojima, K Kangawa, K Shiota and N Murakami
Ghrelin in neonatal rats: distribution in stomach and its
possible role
J. Endocrinology 173: 239-245
N Murakami, T Hayashida, T Kuroiwa,
K Nakahara, T Ida, M S Mondal, M Nakazato, M Kojima, K Kangawa
Role for central ghrelin in food
intake and secretion profile of stomach
ghrelin in rats
J.Endocrinology. 174, 283-288, 2002
Y Date, N Murakami, A Nijima, S
Matsukura, H Matsuo, K Kangawa
M Nakazato
The role of gastric vagal afferent in feeding and growth
hormone secretion
effects of ghrelin.
Gastroenterology.123(4):1120-1128, 2002
JC Rivero, Y Inoue, N
Murakami and Y Horii
Androgen- and estrogen
dependent sex difference in host resistance to Strongyloides venezuelensis
infection in Wistar rats
J . Vet. Med.
Sci. 64: 457-461, 2002
JC Rivero, Y Inoue, N
Murakami and Y Horii
Age- and sex-related changes
in susceptibity of Wistar rats to Strongyloides venezuelensis infection
J . Vet. Med. Sci. 64: 519-521, 2002
2001
N. Murakami, T. Kawano, K. Nakahara, K. Shiota
Effect of melatonin on the circadian rhythm, locomotor
activity and body temperature in intact house sparrow, Japanese quail and owl.
Brain Res 889(1-2):220-224, 2001
M.Nakazato, N.Murakami, Y.Date, M.Kojima, H. Matsuo,
K.Kangawa, S. Matsukura:
A role for
ghrelin in the central regulation of feeding.
Nature 409:194-198, 2001
G Nishimura, K Nakahara, N Misaw, M Muranaka, K Uchida, H Kuroda and N Murakami,
Auto-immunization against
intestinal bacterial endotoxin prevents alcoholic fatty liver.
J.Vet. Med. Sci. 63: 275-280, 2001
Y. Date, M. Nakazato, N.
Murakami, M. Kojima, K. Kangawa, S. Matsukura
Ghrelin Acts in the Central
Nervous System to Stimulate Gastric Acid Secretion
Biochem Biophys Res Commun 280(3):904-907,2001
K. Toshinai, M.S. Mondal, M. Nakazato, Y.
Date, N. Murakami, M. Kojima, K. Kangawa. S. Matsukura
Upregulation of ghrelin expression in the
stomach upon fasting, insulin-induced hypoglycemia and leptin administration
Biochem Biophys Res Commun 281:1220-1225,2001
K
Nakahara, N Murakami, E Takigami, T Nasu, T Murakami
and K Shiota
Intracellular Ca2+ signaling
pathway is involved in light-induced phase advance, but may not be in phase
delay, of circadian melatonin rhythm in chick pineal cell.
Journal of Pineal Research 30:234-242, 2001.
T. Hayashida, K. Murakami, K.
Mogi, M. Nishihara, M. Nakazato, M. S. Mondal, Y.Hori, M. Kojima, K. Kangawa
and N. Murakami.
Ghrelin in domestic animals:
distribution in stomach and its possible role
Domestic Animal Endocrinology 21(1):17-24. 2001
R.Hanada, M.Nakazato,
N.Murakami, S.Sakihara, Hyoshimatsu, K.Toshinai, T.Hanada, T.Suda,
K.Kangawa,S.Matsukura,T.Sakata
A role for neuromedin U in
stress response
Biochem Biophys Res Commun.289: 225-228,2001
2000
R. Hanada, M. Nakazato, S. Matsukura, N. Murakami, H. Yoshimatsu,
T Sakata
Differential regulation of melatnin-concentrating hormone and
orexin genes in the agouti-related protein/melanocortin-4 receptor system
Biochemical and Biophysical Research Communication 268(1): 89-91, 2000
N Murakami, R Kono, K Nakahara, T Ida and H Kuroda
Induction
of Unseasonable Hibernation and Involvement of Serotonin in Entrance into and
Maintenance of Its Hibernation of Chipmunks
T. asiaticus
Journal of Veterinary Medical
Science.62
(7): 763-766, 2000
T Ida, K Nakahara, T Murakami, R Hanada,
M Nakazato and N Murakami
Possible
involvement of orexin in the stress reaction in rats
Biochemical
and Biophysical Research Communications 270 (1): 318-323, 2000
T.Katayama, H.
Kyan, M. Nakashima, E.Y. Rahayu, N. Murakami and H. Kuroda
Involvement of
distinct signaling pathways in activin-induced increases in FSH secretion and
enlargement of FSH cell population in the rat pituitary.
Endocrine
Journal, 47:239-247、2000
T.Katayama, M.
Nakashima, H. Kyan, N. Murakami and H. Kuroda
A role of
pituitary adenylate cyclase activating polypeptide (PACAP) as a regulator of
paracrine interactions between folliclulo-stellate cells and gonadotropes through
the control of activin-follistatin interactions.
J. Vet. Med.
Sci.62:693-698,
2000
Y.Date,
N.Murakamimi, M.Kojima, T.Kuroiwa, S.Mtsukura and M.Nakazato
Central effects
of a novel acylated peptide, ghrelin, on growth hormone release in rats.
Biochemical and Biophysical Research Communications
275:477-480,2000
T. Ida, K. Nakahara, T. Kuroiwa, M. Nakazato, T. Murakami and N. Murakami
Both corticotropin releasing factor (CRF) and neuropeptide
Y (NPY) are involved in the effect of orexin (hypocretin) on the food intake in
rats.
Neuroscience
Letters
293(2):119-122, 2000
M.Kojima, R.Haruno, M.Nakazato, Y.Date, N.Murakami, R.Hanada,
H.Matsuo, K. Kangawa
Purification and identification of neuromedin U as an
andogenous ligand for an orphan receptor GPR66(FM3)
Biochemical and Biophysical Research Communications
276: 435-438, 2000
Nakazato M, Hanada R, Murakami
N, Date Y, Mondal M. S., Kojima M, Yoshimatsu H, Kangawa K, Matsukura S:
Central effects of neuromedin
U in the regulation of energy homeostasis.
Biochem Biophys Res Commun, 277:191-194,
2000
1999
M.K. Ashraf, N.Murakami
Effect of natal dispersal on the reproductive strategies of the
young Misaki feral stallions.
Applied Animal Behaviour Science.
62:281-291,1999
K. Uchida, M. Murayama, Y.Horii, N.Murakami, R. Yamaguchi, S.
Tateyama
Non-purulent meningoencephalomyelitis of a pacific striped dolphin
(Langenorhynchus Obliquidens).The
first evidence of dolphin morbillivirus infection in the pacific ocean around
Japan.
J. Vet. Med. Sci. 61(2) : 159-162,
1999
T. Ida, K. Nakahara, T. Katayama, N. Murakami and M. Nakazato
Effect of lateral cerebroventricular injection of appetite
stimulating neuropeptide, orexin and neuropeptide Y, on the various behavioral
patterns in rats.
Brain Research 821:526-529,1999
M.S. Mondal, M. Nakazato, Y. Date, N. Murakami, M. Yanagisawa, S.
Matsukura
Widespread distribution of orexin in rat brain and its regulation
upon fasting
Biochemical and Biophysical Research Communication 256(3):495-499,1999
M. K. Ashraf, N. Murakami
Factors affecting the harem formation process by young Misaki
feral stallions.
J. Vet. Med. Sci .61(6): 667-671,
1999,
M.S.
Mondal, M. Nakazato, Y. Date, N. Murakami, R. Hanada, T. Sakata, S. Matsukura
Characterization of orexin-A and orexin-B in the microdissected rat brain
nuclei and their contents in two
obese rat models.
Neuroscience Letters 270; 1-4, 1999