Zawilska J B, Woldan-Tambor A, Sek B, Orszulak-Michalak D, Mackova M, Nowak J Z
Department of Biogenic Amines, Polish Academy of Sciences, Lódź, Poland.
Acta Neurobiol Exp (Wars). 1996;56(3):691-5. doi: 10.55782/ane-1996-1173.
The levels of histamine (HA) and tele-methylhistamine (t-MeHA) in chick pineal gland were measured by RIA at two time points, i.e. at the end of the light (L) phase and in the middle of the dark (D) phase of 12 h: 12 h L:D cycle. The chick pineal gland showed high HA levels (12.19 and 13.09 ng/pineal at L and D, respectively). The t-MeHA content of chick pineal gland was about 20-times lower than HA level (650.2 and 536.4 pg/pineal at L and D, respectively). An aminoacid precursor of HA, L-histidine (1 g/kg, ip), given to chicks during L or D significantly increased both HA and t-MeHA content of the pineal gland. The L-histidine-evoked elevations in HA level were 2-4-times higher than changes in t-MeHA content. Enzymatic study showed the presence in chick pineal of a moderate activity of L-histidine decarboxylase (HDC), and well expressed activity of HA-methyltransferase (HMT), HA synthesizing and inactivating enzyme, respectively, which suggests that both HA and t-MeHA may be produced within the gland. It is suggested that the metabolic dynamics of the pineal HA may be higher during lighthours than darkhours of the daily light:dark illumination cycle.
在12小时光照：12小时黑暗（L:D）循环中，在光照（L）阶段结束时和黑暗（D）阶段中期这两个时间点，通过放射免疫分析法（RIA）测定雏鸡松果体中组胺（HA）和 tele-甲基组胺（t-MeHA）的水平。雏鸡松果体显示出较高的HA水平（L期和D期分别为12.19和13.09 ng/松果体）。雏鸡松果体中t-MeHA的含量比HA水平低约20倍（L期和D期分别为650.2和536.4 pg/松果体）。在L期或D期给雏鸡注射HA的氨基酸前体L-组氨酸（1 g/kg，腹腔注射），可显著增加松果体中HA和t-MeHA的含量。L-组氨酸引起的HA水平升高比t-MeHA含量变化高2-4倍。酶学研究表明，雏鸡松果体中存在中等活性的L-组氨酸脱羧酶（HDC），以及表达良好的HA甲基转移酶（HMT）活性，HMT分别是HA合成和失活酶，这表明HA和t-MeHA都可能在腺体内产生。有人提出，在每日光照：黑暗照明周期中，光照期间松果体HA的代谢动力学可能比黑暗期间更高。
