Santos Ana Alice D, Chiarini-Garcia Hélio, Oliveira Karine R, Machado Conceição R S
Department of Morphology, Federal University of Uberlândia, PO Box 593-38400-066, Uberlândia, MG, Brazil.
Anat Embryol (Berl). 2003 Feb;206(3):239-45. doi: 10.1007/s00429-002-0293-2. Epub 2003 Jan 17.
Previous studies have disclosed three types of mast cell in opossums: connective tissue (CTMC), mucosal (MMC), and lymphatic sinus (LSMC). In contrast to most opossum lymph nodes, the mesenteric lymph node is virtually devoid of LSMC, displaying medullary cord CTMC. The present study aimed to describe the development of these mast cell populations. Toluidine blue staining and a histochemical method for demonstrating heparin allowed the identification of immature and mature mast cells. Immature CTMC devoid of detectable heparin were rare until postnatal day 10. Mature CTMC filled with heparin-containing granules became numerous by day 30 to day 40. In the ileum, despite the presence of mature CTMC in the submucosa and mucosa (villus base), immature mast cells first appeared in the villus core by day 65 and adult features were apparent by day 100. In LSMC-containing lymph nodes, immature mast cells were found in lymphatic sinuses by day 10. Clear signs of LSMC differentiation were observed from day 20. Compared with the 10-day value, the mean diameter of cytoplasmic granules at day 40 had doubled and that at day 110 had tripled. In the mesenteric lymph nodes, immature mast cells differentiated into lymphatic sinus CTMC-like cells. After day 80, most of them were located in medullary cords. Weaning and complete maturation of mucosa preceded the differentiation of MMC. In lymph nodes, LSMC differentiation occurred in parallel with the development of the medullary region and deep cortex units.
结缔组织肥大细胞（CTMC）、黏膜肥大细胞（MMC）和淋巴窦肥大细胞（LSMC）。与大多数负鼠淋巴结不同，肠系膜淋巴结实际上没有LSMC，而是显示出髓索CTMC。本研究旨在描述这些肥大细胞群体的发育过程。甲苯胺蓝染色和一种用于显示肝素的组织化学方法可用于识别未成熟和成熟的肥大细胞。在出生后第10天之前，缺乏可检测到的肝素的未成熟CTMC很少见。到第30天至第40天，充满含肝素颗粒的成熟CTMC数量增多。在回肠中，尽管黏膜下层和黏膜（绒毛基部）存在成熟的CTMC，但未成熟的肥大细胞在第65天首次出现在绒毛核心，到第100天呈现出成年特征。在含有LSMC的淋巴结中，未成熟的肥大细胞在第10天出现在淋巴窦中。从第20天开始观察到LSMC分化的明显迹象。与第10天的值相比，第40天细胞质颗粒的平均直径增加了一倍，第110天增加了两倍。在肠系膜淋巴结中，未成熟的肥大细胞分化为淋巴窦CTMC样细胞。80天后，它们大多位于髓索中。MMC的分化发生在断奶和黏膜完全成熟之后。在淋巴结中，LSMC的分化与髓质区域和深层皮质单位的发育同时发生。
