scholarly journals Ultrastructural Study of Post-Hatching Development in the Pineal Gland of the Japanese Quail.

1993 ◽  
Vol 55 (6) ◽  
pp. 945-950 ◽  
Author(s):  
Koji OHSHIMA ◽  
Kohzy HIRAMATSU
Keyword(s):  
Pineal Gland ◽  
Japanese Quail ◽  
Ultrastructural Study

Ultrastructural study of the distribution of calcium in the pineal gland of the rat subjected to manipulation of the photoperiod

1989 ◽  
Vol 92 (2) ◽  
pp. 161-169 ◽  
Author(s):  
M. D. L. Pizarro ◽  
F. E. Pastor ◽  
A. L�pez Gil ◽  
L. Mu�oz Barrag�n
Keyword(s):  
Pineal Gland ◽  
Ultrastructural Study

Circadian rhythm of melatonin in the pineal gland of the Japanese quail (Coturnix coturnix japonica)

1985 ◽  
Vol 107 (3) ◽  
pp. 317-324 ◽  
Author(s):  
J. F. Cockrem ◽  
B. K. Follett
Keyword(s):  
Circadian Rhythm ◽  
Pineal Gland ◽  
Japanese Quail ◽  
Dark Period ◽  
Coturnix Japonica ◽  
Coturnix Coturnix Japonica ◽  
Dark Cycle ◽  
Coturnix Coturnix ◽  
Melatonin Rhythm ◽  
Pineal Melatonin

ABSTRACT Melatonin was measured by radioimmunoassay in homogenates of pineal glands from quail (Coturnix coturnix japonica) kept under different photoperiods and in darkness. Under 8-, 12- and 16-h daylengths melatonin levels were increased during the dark period, the duration of the increase depending on the duration of the dark period. As the daylength was increased the peak occurred closer to lights-off, reflecting the more rapid melatonin rise under the longer photoperiods. The pineal melatonin rhythm continued in darkness with an amplitude relative to that seen under a light/dark cycle of slightly less than one-half after 2 days in darkness and one-third after 6 days in darkness. The corresponding average periods of the rhythm were 25·5 h and 25·7 h. These results show that there is a circadian rhythm of melatonin in the pineal gland of the quail which is entrained by light/dark cycles and which continues in darkness. J. Endocr. (1985) 107, 317–324

The pineal gland and the photoperiodic control of luteinizing hormone secretion in intact and castrated Japanese quail

1983 ◽  
Vol 99 (2) ◽  
pp. 281-287 ◽  
Author(s):  
S. M. Simpson ◽  
H. F. Urbanski ◽  
J. E. Robinson
Keyword(s):  
Pineal Gland ◽  
Japanese Quail ◽  
Prolonged Exposure ◽  
Hormone Secretion ◽  
Quantitative Relationship ◽  
Luteinizing Hormone Secretion ◽  
Photoperiodic Responses ◽  
Induced Changes ◽  
Lh Secretion ◽  
Sexually Mature

The effects of pinealectomy on a range of photoperiodic responses were investigated in male Japanese quail by measuring plasma LH concentrations in intact, sham-operated and pinealectomized birds in the following four experiments: (1) transfer of sexually quiescent birds from a short photoperiod of 8 h light: 16 h darkness (8L: 16D) to a photostimulatory daylength of 16L: 8D; (2) transfer of sexually mature birds from 16L: 8D to 8L: 16D; (3) castration in 16L: 8D and exposure to 13L: 11D; (4) castration in 8L: 16D and exposure to 13L: 11D. There was no evidence of effects of the pineal gland on the photoperiodically induced changes in LH secretion, the quantitative relationship between LH secretion and photoperiod in intact and castrated birds, or the induction of relative photorefractoriness by prolonged exposure to 16L: 8D. This suggests that there is no pineal influence on the photoperiodic clock or its effectors in this bird.

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