Youbicier-Simo B J, Boudard F, Mékaouche M, Baylé J D, Bastide M
Laboratoire de Physiologie Générale, Université de Montpellier II, France.
J Pineal Res. 1996 Aug;21(1):35-43. doi: 10.1111/j.1600-079x.1996.tb00268.x.
The tripeptide bursin (Lys-His-Gly-NH2) is a B cell differentiation hormone derived from the bursa fabricii. The latter is a cloacal diverticulum and the site of B lymphocyte differentiation and selection in aves; also the bursa fabricii is involved in endocrine functions. Herein we demonstrate that in the chicken, the bursa fabricii and bursin are crucial to the ontogeny of both the pineal response to antigenic challenge and pineal circadian synthetic activity. In early embryonically bursectomized chickens, the plasma melatonin response to immunization by porcine thyroglobulin (Tg) was abolished. Also, the amplitudes of both plasma melatonin and pineal N-acetyltransferase (NAT) circadian rhythms were reduced by 50%, whereas the activity of hydroxyindole-O-methyltransferase (HIOMT) remained unchanged. Conversely, administration of either minute amounts (100 pg, 100 fg) or highly dilute (5 x 10(-27) g) bursin, with the exception of a highest dose (100 micrograms), to bursaless embryos induced recovery of normal antigen-induced melatonin response and normal amplitudes of melatonin and NAT rhythms. These findings establish that early in embryonic life, the bursa fabricii and its derived signal (bursin) are essential for normal development of pineal synthetic activity and underline the efficacy of very dilute bursin as an informative signal.
三肽腔上囊素（Lys-His-Gly-NH2）是一种源自腔上囊的B细胞分化激素。腔上囊是泄殖腔憩室，也是鸟类B淋巴细胞分化和选择的部位；此外，腔上囊还参与内分泌功能。在此我们证明，在鸡体内，腔上囊和腔上囊素对于松果体对抗原刺激的反应以及松果体昼夜合成活动的个体发生至关重要。在胚胎早期切除腔上囊的鸡中，血浆褪黑素对猪甲状腺球蛋白（Tg）免疫的反应被消除。此外，血浆褪黑素和松果体N-乙酰转移酶（NAT）昼夜节律的振幅均降低了50%，而羟基吲哚-O-甲基转移酶（HIOMT）的活性保持不变。相反，向无腔上囊的胚胎施用微量（100 pg，100 fg）或高度稀释（5×10⁻²⁷ g）的腔上囊素（最高剂量100微克除外），可诱导正常的抗原诱导的褪黑素反应以及褪黑素和NAT节律的正常振幅恢复。这些发现表明，在胚胎生命早期，腔上囊及其衍生信号（腔上囊素）对于松果体合成活动的正常发育至关重要，并强调了极稀腔上囊素作为一种信息信号的有效性。
