alexa Neurotransmitters of the retino-hypothalamic tract.
Neurology

Neurology

Journal of Neurology & Neurophysiology

Author(s): Hannibal J

Abstract Share this page

Abstract The brain's biological clock, which, in mammals, is located in the suprachiasmatic nucleus (SCN), generates circadian rhythms in behaviour and physiology. These biological rhythms are adjusted daily (entrained) to the environmental light/dark cycle via a monosynaptic retinofugal pathway, the retinohypothalamic tract (RHT). In this review, the anatomical and physiological evidence for glutamate and pituitary adenylate cyclase-activating polypeptide (PACAP) as principal transmitters of the RHT will be considered. A combination of immunohistochemistry at both the light- and electron-microscopic levels and tract-tracing studies have revealed that these two transmitters are co-stored in a subpopulation of retinal ganglion cells projecting to the retino-recipient zone of the ventral SCN. The PACAP/glutamate-containing cells, which constitute the RHT, also contain a recently identified photoreceptor protein, melanopsin, which may function as a "circadian photopigment". In vivo and in vitro studies have shown that glutamate and glutamate agonists such as N-methyl- D-aspartate mimic light-induced phase shifts and that application of glutamate antagonists blocks light-induced phase shifts at subjective night indicating that glutamate mediates light signalling to the clock. PACAP in nanomolar concentrations has similar phase-shifting capacity as light and glutamate, whereas PACAP in micromolar concentrations modulates glutamate-induced phase shifts. Possible targets for PACAP and glutamate are the recently identified clock genes Per1 and Per2, which are induced in the SCN by light, glutamate and PACAP at night. This article was published in Cell Tissue Res and referenced in Journal of Neurology & Neurophysiology

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Relevant Topics

Peer Reviewed Journals
 
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
 
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

Agri, Food, Aqua and Veterinary Science Journals

Dr. Krish

[email protected]

1-702-714-7001 Extn: 9040

Clinical and Biochemistry Journals

Datta A

[email protected]

1-702-714-7001Extn: 9037

Business & Management Journals

Ronald

[email protected]

1-702-714-7001Extn: 9042

Chemical Engineering and Chemistry Journals

Gabriel Shaw

[email protected]

1-702-714-7001 Extn: 9040

Earth & Environmental Sciences

Katie Wilson

[email protected]

1-702-714-7001Extn: 9042

Engineering Journals

James Franklin

[email protected]

1-702-714-7001Extn: 9042

General Science and Health care Journals

Andrea Jason

[email protected]

1-702-714-7001Extn: 9043

Genetics and Molecular Biology Journals

Anna Melissa

[email protected]

1-702-714-7001 Extn: 9006

Immunology & Microbiology Journals

David Gorantl

[email protected]

1-702-714-7001Extn: 9014

Informatics Journals

Stephanie Skinner

[email protected]

1-702-714-7001Extn: 9039

Material Sciences Journals

Rachle Green

[email protected]

1-702-714-7001Extn: 9039

Mathematics and Physics Journals

Jim Willison

[email protected]

1-702-714-7001 Extn: 9042

Medical Journals

Nimmi Anna

[email protected]

1-702-714-7001 Extn: 9038

Neuroscience & Psychology Journals

Nathan T

[email protected]

1-702-714-7001Extn: 9041

Pharmaceutical Sciences Journals

John Behannon

[email protected]

1-702-714-7001Extn: 9007

Social & Political Science Journals

Steve Harry

[email protected]

1-702-714-7001 Extn: 9042

 
© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version
adwords