(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



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



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-G9692003


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. 



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



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



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, 47239-2472000


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




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