Biomaterial Database

Lowering glucose concentrations increases cytosolic Ca2+ in orexin neurons of the rat lateral hypothalamus. 2001

S Muroya, and K Uramura, and T Sakurai, and M Takigawa, and T Yada

Department of Physiology, Jichi Medical School, Minamikawachi, Kawachi, Tochigi 329-0498, Japan.

Orexin neurons are specifically localized in and around the lateral hypothalamus (LH), a feeding center. Intracerebroventricular administration of orexin-A and -B stimulates feeding as well as arousal. However, little is known regarding the regulators of the orexin neuron activity. The neurons that are activated under low glucose conditions, glucose-sensitive neurons, are located in the LH and have been implicated in the control of feeding. The present study investigated the effect of glucose on the single orexin neurons isolated from the rat LH, by measuring cytosolic Ca(2+) concentration ([Ca(2+)](i)) by fura-2 microfluorometry followed by immunocytochemical staining with anti-orexin antiserum. A shift of glucose concentration form 8.3 to 2.8 mM in the superfusion solution increased [Ca(2+)](i) in 13 out of 32 orexin-immunoreactive LH neurons. The results demonstrate that glucose-sensitive orexin neurons are present in the LH and that these neurons may play a role in linking the metabolic state in the body to the orexigenic, and could also, awakening signaling in the brain.

UI	MeSH Term	Description	Entries
D007026	Hypothalamic Area, Lateral	Area in the hypothalamus bounded medially by the mammillothalamic tract and the anterior column of the FORNIX (BRAIN). The medial edge of the INTERNAL CAPSULE and the subthalamic region form its lateral boundary. It contains the lateral hypothalamic nucleus, tuberomammillary nucleus, lateral tuberal nuclei, and fibers of the MEDIAL FOREBRAIN BUNDLE.	Lateral Hypothalamic Area,Lateral Hypothalamic Nucleus,Tuberomammillary Nucleus,Accessory Nucleus of the Ventral Horn,Area Hypothalamica Lateralis,Area Lateralis Hypothalami,Lateral Hypothalamus,Lateral Tuberal Nuclei,Lateral Tuberal Nucleus,Area Hypothalamica Laterali,Area Lateralis Hypothalamus,Area, Lateral Hypothalamic,Areas, Lateral Hypothalamic,Hypothalami, Area Lateralis,Hypothalamic Areas, Lateral,Hypothalamic Nucleus, Lateral,Hypothalamica Laterali, Area,Hypothalamica Lateralis, Area,Hypothalamus, Area Lateralis,Hypothalamus, Lateral,Lateral Hypothalamic Areas,Laterali, Area Hypothalamica,Lateralis Hypothalami, Area,Lateralis Hypothalamus, Area,Lateralis, Area Hypothalamica,Nuclei, Lateral Tuberal,Nucleus, Lateral Hypothalamic,Nucleus, Lateral Tuberal,Nucleus, Tuberomammillary,Tuberal Nuclei, Lateral,Tuberal Nucleus, Lateral
D008297	Male		Males
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
D009479	Neuropeptides	Peptides released by NEURONS as intercellular messengers. Many neuropeptides are also hormones released by non-neuronal cells.	Neuropeptide
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002352	Carrier Proteins	Proteins that bind or transport specific substances in the blood, within the cell, or across cell membranes.	Binding Proteins,Carrier Protein,Transport Protein,Transport Proteins,Binding Protein,Protein, Carrier,Proteins, Carrier
D003600	Cytosol	Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.	Cytosols
D005947	Glucose	A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.	Dextrose,Anhydrous Dextrose,D-Glucose,Glucose Monohydrate,Glucose, (DL)-Isomer,Glucose, (alpha-D)-Isomer,Glucose, (beta-D)-Isomer,D Glucose,Dextrose, Anhydrous,Monohydrate, Glucose
D000068797	Orexins	Neuropeptide hormones that play a role in regulating a variety of behavioral and physiological processes in response to motivational stimuli.	Hypocretin,Orexin,Hypocretin-1,Hypocretin-2,Hypocretins,Orexin-A,Orexin-B,Hypocretin 1,Hypocretin 2,Orexin A,Orexin B
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia