Di Matteo L, Minucci S, Chieffi Baccari G, Pellicciari C, d'Istria M, Chieffi G
Instituto di Biologia, I Facoltà di Medicina e Chirurgia, Università di Napoli, Italy.
Basic Appl Histochem. 1989;33(2):93-112.
The Harderian gland in Rana esculenta has been studied during the annual cycle at the histological, histochemical and ultrastructural levels. The Harderian gland has an acinar structure and is the only orbital gland in anuran amphibia. It develops at the medial corner of the orbit from the conjunctival epithelium at the premetamorphic stage. In the adult the glandular secretion reaches a maximum during the months of July and August, drops in September and resumes slowly from October onwards. The secretion is seromucoid and the secretory granules are released into the acinar lumen, mainly by exocytosis. Porphyrins were not detected. No sexual dimorphism was observed in the glandular cells. The resumption of secretory activity in October and the enhancement of secretion in May are marked by the appearance of "blue nuclei" (Mallory stain) in a relatively high percentage of glandular cells. This unusual blue colour, using the Mallory stain (by which nuclei stain red), disappears after digestion of paraffin sections with RNAase, but not with DNAase and trypsin. The blue staining may, therefore, indicate an increased amount of nuclear RNA. The Harderian gland in the frog most probably serves to lubricate and moisten the eye in the absence of the lacrimal gland. However, the gland may also represent an immunoactive organ owing to the presence of numerous mast cells and plasma cells in the interacinar spaces.
在一年的周期内，对食用蛙的哈德氏腺进行了组织学、组织化学和超微结构水平的研究。哈德氏腺具有腺泡结构，是无尾两栖动物唯一的眶腺。它在变态前阶段从结膜上皮在眼眶内侧角发育而来。在成体中，腺体分泌在7月和8月达到最大值，9月下降，从10月起缓慢恢复。分泌物为浆液性黏液，分泌颗粒主要通过胞吐作用释放到腺泡腔中。未检测到卟啉。在腺细胞中未观察到性别二态性。10月分泌活动的恢复和5月分泌的增强以相对高比例的腺细胞中出现“蓝色细胞核”（马洛里染色）为标志。使用马洛里染色（细胞核染成红色）时这种不寻常的蓝色，在用RNA酶消化石蜡切片后消失，但用DNA酶和胰蛋白酶消化后不消失。因此，蓝色染色可能表明核RNA含量增加。青蛙的哈德氏腺很可能在没有泪腺的情况下起到润滑和湿润眼睛的作用。然而，由于腺泡间空间存在大量肥大细胞和浆细胞，该腺体也可能是一个免疫活性器官。
