Chieffi Baccari Gabriella, Falvo Sara, Lanni Antonia, Di Fiore Maria Maddalena, Cioffi Federica, Santillo Alessandra
Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania "Luigi Vanvitelli", 81100 Caserta, Italy.
Department of Science and Technology, University of Sannio, 82100 Benevento, Italy.
Animals (Basel). 2022 Jul 20;12(14):1840. doi: 10.3390/ani12141840.
The morphological features and relative number of mast cells (MCs) were studied in the skin and exorbital lacrimal glands of hypothyroid Wistar rats, . Hypothyroidism significantly increased the number of MCs (up to 4.5-fold) and histamine content (up to 50%) in the examined tissues. The magnitude of the increase in the number of MCs was greater in the cheek skin and exorbital lacrimal glands than in the back skin. In the skin, the MCs were mainly located within the hypodermis and closely associated with the blood vessels, nerve fascicles, and adipocytes. In the exorbital lacrimal gland, which is a seromucous gland located lateral to the cheek below the ear, the MCs were distributed in the connective tissue surrounding the acini. The secretory granules of MCs showed histochemical characteristics of connective tissue MCs. They were metachromatic with Toluidine blue and safranin positive with the Alcian blue/safranin reactions. Finally, a significant increase in degranulating MCs was observed in hypothyroid tissues, relative to euthyroid tissues. At the ultrastructural level, the MCs of euthyroid rats were predominantly non-degranulating (Stage I). In hypothyroid animals, numerous MCs showed partial degranulation (Stage II-III) or were in a stage of complete degranulation. Our results concerning the skin and exorbital lacrimal gland suggested that the thyroid status might be involved in regulating the frequency and activation state of MCs.
对甲状腺功能减退的Wistar大鼠的皮肤和眶外泪腺中肥大细胞（MCs）的形态特征和相对数量进行了研究。甲状腺功能减退显著增加了所检查组织中MCs的数量（高达4.5倍）和组胺含量（高达50%）。脸颊皮肤和眶外泪腺中MCs数量增加的幅度大于背部皮肤。在皮肤中，MCs主要位于皮下组织内，并与血管、神经束和脂肪细胞紧密相关。眶外泪腺是位于耳下方脸颊外侧的浆液黏液腺，MCs分布在腺泡周围的结缔组织中。MCs的分泌颗粒显示出结缔组织MCs的组织化学特征。它们用甲苯胺蓝染色呈异染性，用阿尔辛蓝/番红反应呈番红阳性。最后，相对于甲状腺功能正常的组织，在甲状腺功能减退的组织中观察到脱颗粒MCs显著增加。在超微结构水平上，甲状腺功能正常大鼠的MCs主要为非脱颗粒状态（I期）。在甲状腺功能减退的动物中，大量MCs显示出部分脱颗粒（II - III期）或处于完全脱颗粒阶段。我们关于皮肤和眶外泪腺的研究结果表明，甲状腺状态可能参与调节MCs的频率和激活状态。
