Pineal enzymes in chickens: Development of daily rhythmicity

doi:10.1016/0016-6480(75)90063-5

General and Comparative Endocrinology

Volume 27, Issue 4, December 1975, Pages 424-429

https://doi.org/10.1016/0016-6480(75)90063-5 Get rights and content

Abstract

Pineal serotonin N-acetyltransferase activity and HIOMT (hydroxyindole-O-methyl-transferase) activity were measured in chicks (White Leghorn Gallus domesticus) over a period of 8 weeks from the day of hatching. The measurements were made at two time points on selected days: one time point was taken during the light portion of the birds' environmental lighting regime, the other point was taken during the dark portion (1000 and 1600, respectively, in an LD12 : 12 cycle with lights-off at 1200 and lights-on at 2400). There were no dramatic differences in HIOMT activity between the light and dark measurements on any day, though the enzyme activity rose steadily with age. Changes were always seen in N-acetyltransferase activity in light versus dark. Dark-time N-acetyltransferase activity was higher than light-time activity. This includes the initial exposure of the chicks to dark on day 2 after hatching. N-acetyltransferase activity was also measured in the pineal glands of chick embryos kept in LD12 : 12. In embryos incubated for 17 and 19 days the dark-time values for enzyme activity were almost twice the light-time values.

References (21)

L. Hedlund et al.
A diurnal serotonin cycle in the pineal body of Japanese Quail: Photoperiod phasing and the effect of superior cervical ganglionectomy
Gen. Comp. Endocrinology
(1971)
W.B. Quay
Rhythmic and light-induced changes in levels of pineal 5-hydroxyindoles in the pigeon
Gen. Comp. Endocrinology
(1966)
C.L. Ralph et al.
Diurnal cycles of melatonin in bird pineal bodies
Comp. Biochem. Physiol
(1967)
J. Axelrod et al.
Melatonin synthesis in the hen pineal gland and its control by light
Nature (London)
(1964)
J. Axelrod et al.
Control of Hydroxyindole O-methyltransferase activity in the rat pineal gland by environmental lighting
J. Biol. Chem
(1965)
S. Binkley et al.
Pineal N-acetyltransferase in chickens: Rhythm persists in constant darkness
J. Comp. Physiol
(1975)
S. Binkley et al.
Pineal serotonin N-acetyltransferase activity: Protection of stimulated activity by acetyl-CoA and related compounds
J. Neurochem
(1975)
S. Binkley et al.
Pineal enzymes: Regulation of avian melatonin synthesis
Science
(1973)
S. Binkley et al.
Regulation of pineal rhythms in chickens: Refractory period and non-visual light perception
Endocrinology
(1975)
N. Ellison et al.
Development of a circadian rhythm in the activity of pineal serotonin N-acetyltransferase
J. Neurochem
(1972)

There are more references available in the full text version of this article.

Cited by (40)

Circadian melatonin production develops faster in birds than in mammals
2011, General and Comparative Endocrinology
Citation Excerpt :
In contrast to the known situation in mammals, daily rhythms of melatonin biosynthesis have been observed in the embryonic pineal gland. A twofold day–night difference in activity of arylalkylamine N-acetyltransferase (AA-NAT) was reported in the pineal gland of 17- and 19-day-old chick embryos [10]. This enzyme catalyzes the formation of a melatonin precursor, N-acetylserotonin, from serotonin and is responsible for rhythmic melatonin production [38].
The development of circadian rhythmicity of melatonin biosynthesis in the pineal gland starts during embryonic period in birds while it is delayed to the postnatal life in mammals. Daily rhythms of melatonin in isolated pinealocytes and in intact pineal glands under in vivo conditions were demonstrated during the last third of embryonic development in chick embryos, with higher levels during the dark (D) than during the light (L) phase. In addition to the LD cycle, rhythmic temperature changes with the amplitude of 4.5 °C can entrain rhythmic melatonin biosynthesis in chick embryos, with higher concentrations found during the low-temperature phase (33.0 vs 37.5 °C). Molecular clockwork starts to operate during the embryonic life in birds in line with the early development of melatonin rhythmicity. Expression of per2 and cry genes is rhythmic at least at day 16 and 18, respectively, and the circadian system operates in a mature-like manner soon after hatching. Rhythmic oscillations are detected earlier in the central oscillator (the pineal gland) than in the peripheral structures, reflecting the synchronization of individual cells which is necessary for detection of the rhythm. The early development of the circadian system in birds reflects an absence of rhythmic maternal melatonin which in mammals synchronizes physiological processes of offspring. Developmental consequences of modified development of circadian system for its stability later in development are not known and should be studied.
Ontogeny of circadian clock gene expression in the pineal and the suprachiasmatic nucleus of chick embryo
2003, Brain Research
Avian circadian rhythms are regulated by a multiple oscillatory system consisting of the pineal, the suprachiasmatic nucleus (SCN) and the eye. In the present study, ontogeny of circadian clock in the pineal and the SCN of chick embryo was examined using Per2 expression as a marker. A daily rhythmicity of Per2 expression was first detectable at embryonic day (ED) 18 in the pineal and at ED 16 in the SCN under light–dark (LD) cycles. The amplitude of the rhythmicity increased during the development. In contrast, little expression was observed during the development in constant darkness. These results suggest that although circadian clock matures by the end of the embryonic life in chicken, LD cycles are required for the expression of the Per2.
Rhythms of the pineal N-acetyltransferase mRNA and melatonin concentrations during embryonic and post-embryonic development in chicken
2001, Neuroscience Letters
Development of a daily rhythmicity in transcription of a gene encoding a rate-limiting enzyme of melatonin biosynthesis, the arylalkylamine-N-acetyltransferase (AA-NAT) was studied by northern blot analysis in pineal glands of 16 and 19-day-old embryos and 1, 4, 8, 11, and 14-day-old chicks. In a parallel experiment, melatonin content in pineal glands and plasma was measured. A significant rhythm of AA-NAT expression was found at embryonic day (ED) 16, the earliest day assayed in this experiment. Expression was low during the daytime and a clear signal was found in the middle of the darktime. The intensity of the signal was increasing during the ontogeny. The nocturnal pineal melatonin concentrations were increasing over the studied period (from ED 19 until post-embryonic day 21). Midnight plasma melatonin concentrations increased from ED19 to PD 3 and oscillated around this value afterwards. Data show that rhythmic expression of AA-NAT mRNA starts very early in development of chicken and plays a major role in melatonin rhythm generation during embryonic development.
Cellular circadian clocks in the pineal
1999, Progress in Neurobiology
Daily rhythms are a fundamental feature of all living organisms; most are synchronized by the 24 hr light/dark (LD) cycle. In most species, these rhythms are generated by a circadian system, and free run under constant conditions with a period close to 24 hr. To function properly the system needs a pacemaker or clock, an entrainment pathway to the clock, and one or more output signals.
In vertebrates, the pineal hormone melatonin is one of these signals which functions as an internal time-keeping molecule. Its production is high at night and low during day, a pattern well preserved in vertebrates.
Evidence indicates that each melatonin producing cells of the pineal constitutes a circadian system per se in non-mammalian vertebrates. In addition to the melatonin generating system, they contain the clock as well as the photoreceptive unit. This is despite the fact that these cells have been profoundly modified from fish to birds.
Modifications include a regression of the photoreceptive capacities, and of the ability to transmit a nervous message to the brain. The ultimate stage of this evolutionary process leads to the definitive loss of both the direct photosensitivity and the clock, as observed in the pineal of mammals.
This review focuses on the functional properties of the cellular circadian clocks of non-mammalian vertebrates. How functions the clock? How is the photoreceptive unit linked to it and how is the clock linked to its output signal? These questions are addressed in light of past and recent data obtained in vertebrates, as well as invertebrates and unicellulars.
Hydroxyindole-O-methyltransferase gene expression in the pineal gland of chicken embryo: development of messenger RNA levels and regulation by serum
1995, Developmental Brain Research
Hydroxyindole-O-methyltransferase (HIOMT), the enzyme which catalyzes the final step of melatonin biosynthesis, constitutes a marker of the functional differentiation of pineal cells. In addition, a day/night rhythm of HIOMT mRNA concentration, previously described in the chicken pineal gland [6], would suggest that HIOMT gene transcription is one output of the circadian system that controls pineal function. The present study sought to monitor the developmental expression of HIOMT mRNA in the chick pineal gland and to investigate a possible role of instructive signals in this differentiation process. RT-PCR analysis indicated that HIOMT mRNA is expressed at embryonic day 8 (E8). At E12, HIOMT mRNA became detectable on northern blots and traces of HIOMT activity could be measured. HIOMT mRNA concentration increased 100-fold between E14 and day 10 post-hatch, then levelled off. A day/night rhythm of HIOMT mRNA concentration was readily observed in the pineal gland of 2-day-old chicks. Pineal glands isolated on minimum culture medium at E11 stopped developing HIOMT gene expression. However, the addition of serum to the culture medium restored HIOMT mRNA concentration to the levels observed in vivo. The data suggest that the functional differentiation of melatoninergic cells observed during the second week of embryonic life may be controled by serum factors.
Development of regulation of melatonin release in pineal cells in chick embryo
1995, Brain Research
Melatonin release in a pineal cell culture from 13- and 14-day-old chick embryos increased during the dark phase and decreased during the light phase of a 12 h light:12 h dark cycle. When the light-dark cycle was reversed, the pattern of melatonin release in the culture also reversed. 8-Bromo cyclic-AMP stimulated melatonin release in both the light and dark phases. However, no rhythm of melatonin release was detected under constant dark (DD) conditions in a cell culture from 14-day-old chick embryos. In 18-day-old chick embryos, the pineal cell culture expressed a circadian rhythm of melatonin release under DD conditions. These results indicate that mechanisms regulating melatonin synthesis in the avian pineal gland are established during embryonic life.

View all citing articles on Scopus

¹: Present address: % Dr. Martin Adler, Department of Pharmacology, Temple University Medical School, 3420 North Broad Street, Philadelphia, Pa. 19140.

View full text

Pineal enzymes in chickens: Development of daily rhythmicity

Abstract

Gen. Comp. Endocrinology

Gen. Comp. Endocrinology

Comp. Biochem. Physiol

Melatonin synthesis in the hen pineal gland and its control by light

Nature (London)

Control of Hydroxyindole O-methyltransferase activity in the rat pineal gland by environmental lighting

J. Biol. Chem

Pineal N-acetyltransferase in chickens: Rhythm persists in constant darkness

J. Comp. Physiol

Pineal serotonin N-acetyltransferase activity: Protection of stimulated activity by acetyl-CoA and related compounds

J. Neurochem

Pineal enzymes: Regulation of avian melatonin synthesis

Science

Regulation of pineal rhythms in chickens: Refractory period and non-visual light perception

Endocrinology

Development of a circadian rhythm in the activity of pineal serotonin N-acetyltransferase

J. Neurochem