Signal transmission from the suprachiasmatic nucleus to the pineal gland via the paraventricular nucleus: analysed from arg-vasopressin peptide, rPer2 mRNA and AVP mRNA changes and pineal AA-NAT mRNA after the melatonin injection during light and dark periods

2004 ◽  
Vol 1013 (2) ◽  
pp. 204-211 ◽  
Author(s):  
Yoshiaki Isobe ◽  
Hitoo Nishino
Keyword(s):  
Pineal Gland ◽  
Suprachiasmatic Nucleus ◽  
Paraventricular Nucleus ◽  
Signal Transmission ◽  
Melatonin Injection

Pineal physiology and pathophysiology, including pineal tumours

2011 ◽  
pp. 267-272
Author(s):  
Anna Aulinas ◽  
Cristina Colom ◽  
Susan M. Webb
Keyword(s):  
Pineal Gland ◽  
Suprachiasmatic Nucleus ◽  
Third Ventricle ◽  
Hypogonadotropic Hypogonadism ◽  
Delayed Puberty ◽  
Thoracic Spinal ◽  
Neural Input ◽  
Cervical Ganglia ◽  
Upper Thoracic ◽  
Parenchymal Cells

The pineal gland is innervated mainly by sympathetic nerve fibres that inform the gland of the prevailing light-dark cycle and acts as a neuroendocrine transducer. The gland is located behind the third ventricle in the centre of the brain and is a highly vascular organ formed by neuroglial cells and parenchymal cells or pinealocytes. The latter synthesize melatonin as well as other indoleamines and peptides. The main pineal hormone melatonin (N-acetyl-5-methoxytryp-tamine) exhibits an endogenous circadian rhythm, reflecting signals originating in the suprachiasmatic nucleus; environmental lighting entrains the rhythm, by altering its timing. Independently of sleep, pineal melatonin is inhibited by light and stimulated during darkness, thanks to the neural input by a multisynaptic pathway that connects the retina, through the suprachiasmatic nucleus of the hypothalamus, preganglionic neurons in the upper thoracic spinal cord and postganglionic sympathetic fibres from the superior cervical ganglia, with the pineal gland. Melatonin deficiency may produce sleeping disorders, behavioural problems, or be associated with precocious or delayed puberty in children, while chronically elevated melatonin has been observed in some cases of hypogonadotropic hypogonadism (1, 2).

Entrainment of Syrian hamster circadian activity rhythms by neonatal melatonin injections

1996 ◽  
Vol 270 (3) ◽  
pp. R533-R540 ◽  
Author(s):  
J. Grosse ◽  
A. Velickovic ◽  
F. C. Davis
Keyword(s):  
Circadian Rhythms ◽  
Suprachiasmatic Nucleus ◽  
Syrian Hamster ◽  
Circadian Activity ◽  
Syrian Hamsters ◽  
Activity Rhythms ◽  
Vehicle Injection ◽  
Two Phases ◽  
Melatonin Injection

The circadian rhythms of fetal and neonatal rodents are entrained by their mother. This entrainment is dependent upon the maternal suprachiasmatic nucleus (SCN), but the mechanism of entrainment is unknown. Administration of the pineal hormone melatonin to pregnant, SCN-lesioned female Syrian hamsters entrains the activity rhythms of their hamster pups. The aim of this study was to determine whether melatonin injected directly in neonatal Syrian hamsters is able to entrain circadian rhythms and, if so, for how long this effect persists during development. Injection of melatonin in two groups of hamster pups at opposite phases on postnatal days 1-5 entrained the onset of activity rhythms on the day of weaning to two phases 10.67 h apart. Melatonin injection did not entrain activity rhythms to opposite phases on either postnatal days 6-10 or 21-25. Vehicle injection did not entrain animals to opposite phases at any of the ages studied. These results demonstrate that melatonin is able to act directly on the neonate to cause entrainment and that this effect disappears after postnatal day 6.

Daily Torpor Alters Multiple Gene Expression in the Suprachiasmatic Nucleus and Pineal Gland of the Djungarian Hamster (Phodopus sungorus)

2006 ◽  
Vol 23 (1-2) ◽  
pp. 269-276 ◽  
Author(s):  
Annika Herwig ◽  
Florent Revel ◽  
Michel Saboureau ◽  
Paul Pévet ◽  
Stephan Steinlechner
Keyword(s):  
Gene Expression ◽  
Pineal Gland ◽  
Suprachiasmatic Nucleus ◽  
Phodopus Sungorus ◽  
Daily Torpor ◽  
Djungarian Hamster ◽  
Multiple Gene

Entrainment of hamster pup circadian rhythms by prenatal melatonin injections to the mother

1988 ◽  
Vol 255 (3) ◽  
pp. R439-R448 ◽  
Author(s):  
F. C. Davis ◽  
J. Mannion
Keyword(s):  
Circadian Rhythms ◽  
Pineal Gland ◽  
Suprachiasmatic Nucleus ◽  
Experimental Approach ◽  
Physiological Role ◽  
Normal Phase ◽  
Daily Injection ◽  
Circadian Pacemaker ◽  
Prenatal Treatment ◽  
Subcutaneous Injections

A circadian pacemaker, thought to be within the suprachiasmatic nucleus (SCN) of the hypothalamus, begins to function before birth in rodents. Prenatal entrainment of the pacemaker appears to be mediated by signals regulated by the maternal SCN; ablation of the mother's SCN during gestation disrupts the normal phase of the pups' rhythms. The present paper presents an experimental approach for identifying candidate entraining signals and for testing when they are effective during development. The candidate signal examined in these experiments was the pineal gland hormone, melatonin. Female golden hamsters (Mesocricetus auratus) received SCN lesions on day 7 of gestation. During the last week of gestation, they were given two daily subcutaneous injections of oil 12 h apart. One of the injections each day contained melatonin (10, 50, or 100 micrograms). The phases of the pups' activity rhythms were measured at weaning and were found to be related to the timing of the daily injection that contained melatonin, demonstrating that the melatonin directly or indirectly set the phase of the pups' rhythms. Injections given over 4 days of gestation were found to be as effective as injections given over 7 days. Although a physiological role for melatonin as an entraining signal has not been demonstrated, the results show that exogenous, prenatal treatment can predictably set the phase of the offsprings' circadian rhythms.

Cytochrome Oxidase Activity of the Suprachiasmatic Nucleus and Pineal Gland in Rats with Portacaval Shunt

2002 ◽  
Vol 173 (2) ◽  
pp. 275-282 ◽  
Author(s):  
Laudino López ◽  
Héctor González-Pardo ◽  
José Manuel Cimadevilla ◽  
Marı́a Cavas ◽  
Marı́a A. Aller ◽  
...  
Keyword(s):  
Pineal Gland ◽  
Cytochrome Oxidase ◽  
Suprachiasmatic Nucleus ◽  
Oxidase Activity ◽  
Portacaval Shunt ◽  
Cytochrome Oxidase Activity

scholarly journals Circadian Clock Genes and Photoperiodism: Comprehensive Analysis of Clock Gene Expression in the Mediobasal Hypothalamus, the Suprachiasmatic Nucleus, and the Pineal Gland of Japanese Quail under Various Light Schedules

Endocrinology ◽  
2003 ◽  
Vol 144 (9) ◽  
pp. 3742-3748 ◽  
Author(s):  
Shinobu Yasuo ◽  
Miwa Watanabe ◽  
Naritoshi Okabayashi ◽  
Shizufumi Ebihara ◽  
Takashi Yoshimura
Keyword(s):  
Pineal Gland ◽  
Circadian Clock ◽  
Suprachiasmatic Nucleus ◽  
Clock Genes ◽  
Expression Patterns ◽  
Hypothalamic Nucleus ◽  
Mediobasal Hypothalamus ◽  
Clock Gene Expression ◽  
Circadian Clock Genes ◽  
Important Center

Abstract In birds, the mediobasal hypothalamus (MBH) including the infundibular nucleus, inferior hypothalamic nucleus, and median eminence is considered to be an important center that controls the photoperiodic time measurement. Here we show expression patterns of circadian clock genes in the MBH, putative suprachiasmatic nucleus (SCN), and pineal gland, which constitute the circadian pacemaker under various light schedules. Although expression patterns of clock genes were different between long and short photoperiod in the SCN and pineal gland, the results were not consistent with those under night interruption schedule, which causes testicular growth. These results indicate that different expression patterns of the circadian clock genes in the SCN and pineal gland are not an absolute requirement for encoding and decoding of seasonal information. In contrast, expression patterns of clock genes in the MBH were stable under various light conditions, which enables animals to keep a steady-state photoinducible phase.

Circadian profile ofPer gene mRNA expression in the suprachiasmatic nucleus, paraventricular nucleus, and pineal body of aged rats

2001 ◽  
Vol 66 (6) ◽  
pp. 1133-1139 ◽  
Author(s):  
Makoto Asai ◽  
Yuko Yoshinobu ◽  
Satoshi Kaneko ◽  
Akiko Mori ◽  
Takato Nikaido ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Suprachiasmatic Nucleus ◽  
Paraventricular Nucleus ◽  
Pineal Body ◽  
Aged Rats ◽  
Gene Mrna
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