Zawilska J B, Wawrocka M
Department of Pharmacodynamics, Medical University, Lodz, Poland.
Neurosci Lett. 1993 Apr 16;153(1):21-4. doi: 10.1016/0304-3940(93)90067-u.
Oscillations in serotonin N-acetyltransferase (NAT) activity and melatonin content were investigated in retina and pineal gland of chicks kept for 5 days in constant darkness (DD) or continuous light (LL). Under DD the rhythm of the pineal melatonin biosynthesis resembled that found under diurnal illumination (LD), whereas in the retina DD resulted in significant elevations of NAT activity and melatonin level during subjective light. A low-amplitude rhythm of retinal NAT activity continued under LL with a period close to 24 h. In the pineal gland, light exposure suppressed the level of NAT activity and melatonin content (an effect being substantially weaker than that observed in retina), delayed the first peak of NAT activity by 3 h, and prolonged the rhythm's period to about 26 h. Our data suggest the existence of some differences in the activity of circadian oscillators that regulate the melatonin generating system in the retina and pineal gland of chick.
在持续黑暗（DD）或持续光照（LL）条件下饲养5天的雏鸡视网膜和松果体中，研究了血清素N-乙酰转移酶（NAT）活性和褪黑素含量的振荡情况。在DD条件下，松果体褪黑素生物合成的节律类似于在昼夜光照（LD）下发现的节律，而在视网膜中，DD导致主观光照期间NAT活性和褪黑素水平显著升高。在LL条件下，视网膜NAT活性存在低振幅节律，周期接近24小时。在松果体中，光照抑制了NAT活性水平和褪黑素含量（这种效应明显弱于在视网膜中观察到的效应），使NAT活性的第一个峰值延迟3小时，并将节律周期延长至约26小时。我们的数据表明，调节雏鸡视网膜和松果体中褪黑素生成系统的昼夜振荡器的活动存在一些差异。
