Amarales Angel, Meng Rebecca, Perez Marco, Bonilla Michelle, Hernandez Jazmir, de Bellard Maria Elena
Biology, California State University, Northridge, Northridge, California, United States.
Moorpark College, Moorpark, California, United States.
MicroPubl Biol. 2024 Nov 19;2024. doi: 10.17912/micropub.biology.001213. eCollection 2024.
The skin is the most extensive organ in vertebrates, composed of two layers: the epidermis and the dermis. Sensory axons originating from the dorsal root ganglia innervate the skin mechanoreceptors in the dermis. Elasmobranchs, which appeared 380 million years ago, are characterized by rough skin composed of dermal denticles. While we know about the epidermis and dermis of elasmobranchs, we do not know much about the presence or abundance of mechanoreceptors in their skin. Using the classic histological hematoxylin and eosin method, we examined the skins of hatchling embryos and adults Batoidea (skates and rays) and Selachimorpha (modern sharks). Our histology findings provide substantial evidence to identify structures with similar morphology to traditional mammalian and reptilian mechanoreceptors like Pacinian and Meissner corpuscles. An interesting observation was the presence of Pacinian in the skin of Batoidea but not in the skin of a Selachimorpha Squalus shark.
皮肤是脊椎动物中面积最大的器官，由两层组成：表皮和真皮。源自背根神经节的感觉轴突支配真皮中的皮肤机械感受器。出现于3.8亿年前的软骨鱼类，其特征是皮肤粗糙，由皮齿组成。虽然我们了解软骨鱼类的表皮和真皮，但对其皮肤中机械感受器的存在情况或数量知之甚少。我们使用经典的苏木精和伊红组织学方法，检查了鳐形目（鳐鱼和魟鱼）和鼠鲨目（现代鲨鱼）幼体胚胎和成体的皮肤。我们的组织学研究结果提供了大量证据，可识别出与传统哺乳动物和爬行动物的机械感受器（如环层小体和梅克尔小体）形态相似的结构。一个有趣的发现是，在鳐形目的皮肤中存在环层小体，而在鼠鲨目白斑角鲨的皮肤中则没有。
