Biomaterial Database

Clonidine in vivo mimics the acute suppressive but not the phase-shifting effects of light on circadian rhythm of serotonin N-acetyltransferase activity in chick pineal gland. 1994

J B Zawilska

Department of Biogenic Amines, Polish Academy of Sciences, Lódź.

Comparative in vivo studies on effects of pulses of light and clonidine, a selective agonist of alpha 2-adrenergic receptors, on the circadian rhythm of serotonin N-acetyltransferase (NAT) activity in chick pineal gland were performed. Six-hour pulses of white light caused an acute suppression of the nocturnal NAT activity and phase-dependent phase shifts of the circadian rhythm of the enzyme activity relative to controls. Systemic administration of clonidine acutely suppressed NAT activity of chick pineal gland, but did not affect the phase of subsequent cycles in constant darkness. These results give further support to the concept based on in vitro studies that alpha 2-adrenergic receptors are involved in regulation of melatonin biosynthesis in chick pineal gland by a mechanism distal to the pacemaker that generates the circadian melatonin rhythm.

UI	MeSH Term	Description	Entries
D008027	Light	That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.	Light, Visible,Photoradiation,Radiation, Visible,Visible Radiation,Photoradiations,Radiations, Visible,Visible Light,Visible Radiations
D008297	Male		Males
D008550	Melatonin	A biogenic amine that is found in animals and plants. In mammals, melatonin is produced by the PINEAL GLAND. Its secretion increases in darkness and decreases during exposure to light. Melatonin is implicated in the regulation of SLEEP, mood, and REPRODUCTION. Melatonin is also an effective antioxidant.
D010870	Pineal Gland	A light-sensitive neuroendocrine organ attached to the roof of the THIRD VENTRICLE of the brain. The pineal gland secretes MELATONIN, other BIOGENIC AMINES and NEUROPEPTIDES.	Epiphysis Cerebri,Pineal Body,Corpus Pineale,Gland, Pineal,Pineal Bodies,Pineal Glands
D002645	Chickens	Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.	Gallus gallus,Gallus domesticus,Gallus gallus domesticus,Chicken
D002940	Circadian Rhythm	The regular recurrence, in cycles of about 24 hours, of biological processes or activities, such as sensitivity to drugs or environmental and physiological stimuli.	Diurnal Rhythm,Nyctohemeral Rhythm,Twenty-Four Hour Rhythm,Nycthemeral Rhythm,Circadian Rhythms,Diurnal Rhythms,Nycthemeral Rhythms,Nyctohemeral Rhythms,Rhythm, Circadian,Rhythm, Diurnal,Rhythm, Nycthemeral,Rhythm, Nyctohemeral,Rhythm, Twenty-Four Hour,Rhythms, Circadian,Rhythms, Diurnal,Rhythms, Nycthemeral,Rhythms, Nyctohemeral,Rhythms, Twenty-Four Hour,Twenty Four Hour Rhythm,Twenty-Four Hour Rhythms
D003000	Clonidine	An imidazoline sympatholytic agent that stimulates ALPHA-2 ADRENERGIC RECEPTORS and central IMIDAZOLINE RECEPTORS. It is commonly used in the management of HYPERTENSION.	Catapres,Catapresan,Catapressan,Chlophazolin,Clofelin,Clofenil,Clonidine Dihydrochloride,Clonidine Hydrochloride,Clonidine Monohydrobromide,Clonidine Monohydrochloride,Clopheline,Dixarit,Gemiton,Hemiton,Isoglaucon,Klofelin,Klofenil,M-5041T,ST-155,Dihydrochloride, Clonidine,Hydrochloride, Clonidine,M 5041T,M5041T,Monohydrobromide, Clonidine,Monohydrochloride, Clonidine,ST 155,ST155
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
D001191	Arylamine N-Acetyltransferase	An enzyme that catalyzes the transfer of acetyl groups from ACETYL-COA to arylamines. It can also catalyze acetyl transfer between arylamines without COENZYME A and has a wide specificity for aromatic amines, including SEROTONIN. However, arylamine N-acetyltransferase should not be confused with the enzyme ARYLALKYLAMINE N-ACETYLTRANSFERASE which is also referred to as SEROTONIN ACETYLTRANSFERASE.	Arylamine Acetylases,Arylamine Acetyltransferases,Acetyl-CoA Arylamine N-Acetyltransferase,Arylamine Acetylase,Acetyl CoA Arylamine N Acetyltransferase,Acetylase, Arylamine,Acetylases, Arylamine,Acetyltransferases, Arylamine,Arylamine N Acetyltransferase,Arylamine N-Acetyltransferase, Acetyl-CoA,N-Acetyltransferase, Acetyl-CoA Arylamine,N-Acetyltransferase, Arylamine
D018341	Receptors, Adrenergic, alpha-2	A subclass of alpha-adrenergic receptors found on both presynaptic and postsynaptic membranes where they signal through Gi-Go G-PROTEINS. While postsynaptic alpha-2 receptors play a traditional role in mediating the effects of ADRENERGIC AGONISTS, the subset of alpha-2 receptors found on presynaptic membranes signal the feedback inhibition of NEUROTRANSMITTER release.	Adrenergic alpha-2 Receptors,Receptors, alpha-2 Adrenergic,alpha-2 Adrenergic Receptors,Adrenergic Receptor alpha(2C),Adrenergic Receptor alpha(2d),Adrenergic Receptor alpha-2C,Adrenergic Receptor alpha-2b,Adrenergic Receptor, alpha-2,Adrenergic alpha-2A Receptors,Adrenergic alpha-2B Receptors,Adrenergic alpha-2C Receptors,Adrenergic alpha-2D Receptors,Receptor, Adrenergic, alpha-2,Receptor, Adrenergic, alpha-2A,Receptor, Adrenergic, alpha-2B,Receptor, Adrenergic, alpha-2C,Receptor, Adrenergic, alpha-2D,Receptors, Adrenergic, alpha-2A,Receptors, Adrenergic, alpha-2B,Receptors, Adrenergic, alpha-2D,alpha 2 Adrenergic Receptors,alpha-2A Adrenergic Receptor,alpha-2B Adrenergic Receptor,alpha-2C Adrenergic Receptor,alpha-2D Adrenergic Receptor,Adrenergic Receptor alpha 2C,Adrenergic Receptor alpha 2b,Adrenergic Receptor, alpha 2,Adrenergic Receptor, alpha-2A,Adrenergic Receptor, alpha-2B,Adrenergic Receptor, alpha-2C,Adrenergic Receptor, alpha-2D,Adrenergic Receptors, alpha-2,Adrenergic alpha 2 Receptors,Adrenergic alpha 2A Receptors,Adrenergic alpha 2B Receptors,Adrenergic alpha 2C Receptors,Adrenergic alpha 2D Receptors,Receptor alpha-2C, Adrenergic,Receptor alpha-2b, Adrenergic,Receptor, alpha-2 Adrenergic,Receptor, alpha-2A Adrenergic,Receptor, alpha-2B Adrenergic,Receptor, alpha-2C Adrenergic,Receptor, alpha-2D Adrenergic,Receptors, Adrenergic alpha-2,Receptors, Adrenergic alpha-2A,Receptors, Adrenergic alpha-2B,Receptors, Adrenergic alpha-2C,Receptors, Adrenergic alpha-2D,Receptors, alpha 2 Adrenergic,alpha 2A Adrenergic Receptor,alpha 2B Adrenergic Receptor,alpha 2C Adrenergic Receptor,alpha 2D Adrenergic Receptor,alpha-2 Adrenergic Receptor,alpha-2 Receptors, Adrenergic,alpha-2A Receptors, Adrenergic,alpha-2B Receptors, Adrenergic,alpha-2C Receptors, Adrenergic,alpha-2C, Adrenergic Receptor,alpha-2D Receptors, Adrenergic,alpha-2b, Adrenergic Receptor