Jaworska-Adamu J, Krawczyk A, Rycerz K, Gołyński M, Wawrzyniak A, Lutnicki K, Balicki I
Department of Animal Anatomy and Histology, Faculty of Veterinary Medicine, University of Life Sciences, Akademicka 12, 20-033, Lublin, Poland.
Subdepartment of Internal Diseases of Farm Animals and Horses, Faculty of Veterinary Medicine, University of Life Sciences, Głęboka 30, 20-612 Lublin, Poland.
Pol J Vet Sci. 2018 Sep;21(3):469-474. doi: 10.24425/122620.
Calretinin (CR), a calcium-binding protein from EF-hand family, is localised in non-pyramidal GABA-ergic interneurons of the hippocampus. CR takes part in maintaining calcium binding homeostasis, which suggests its neuroprotective role. Hippocampal neurons contain membrane transient receptor potential vanilloid 1 (TRPV1) which binds to capsaicin (CAP) contained in habanero pepper fruits. Few in vivo studies have revealed the effect of CAP on interneurons containing CR. The aim of the present study was to investigate the CR immunoreac- tivity in interneurons of the hippocampal CA1 field and dentate gyrus (DG) in adult rats after intragastric admin- istration of the habanero pepper fruits. Wistar rats received a peanut oil - control group (C), and oil suspension of habanero pepper fruits at doses of 0.025 g dm/kg b.w. - group I and 0.08 g dm/kg b.w. - group II for 28 days. After euthanasia, the brains were collected and embedded in paraffin blocks using a routine histological tech- nique. Frontal hippocampal sections were immunohistochemically stained for CR by using a peroxidase-antiper- oxidase method. CR immunoreactive (CR-IR) interneurons were morphologically and morphometrically ana- lyzed under a light microscope. The results showed similar shapes and distribution of cells in both areas of the brain in group C and I of animals. However, CR-IR interneurons in the hippocampal CA1 field and in DG were occasionally observed in the group II of rats. The results of morphometric studies did not reveal statistically significant differences in the surface area and shape index of cells between examined brain regions from groups I and II compared to group C. Only in group II of rats, an increase in the digital immunostaining intensity of CR-IR interneurons was found in DG. Low number of CR-IR interneurons in the hippocampal CA1 field and in the DG, under the influence of a large dose of habanero pepper fruits containing CAP, may be caused by the activation of TRPV1 receptors and the increase in Ca2+ ions in these cells. This phenomenon may ultimately lead to neuronal death and may disturb neuronal conduction.
钙视网膜蛋白（CR）是一种来自EF手家族的钙结合蛋白，定位于海马体的非锥体GABA能中间神经元中。CR参与维持钙结合稳态，这表明其具有神经保护作用。海马神经元含有膜瞬时受体电位香草酸受体1（TRPV1），它与哈瓦那辣椒果实中含有的辣椒素（CAP）结合。很少有体内研究揭示CAP对含有CR的中间神经元的影响。本研究的目的是调查成年大鼠经胃内给予哈瓦那辣椒果实后，海马CA1区和齿状回（DG）中间神经元中的CR免疫反应性。Wistar大鼠分为：接受花生油的对照组（C），以及接受剂量为0.025 g dm/kg体重的哈瓦那辣椒果实油悬液的I组和剂量为0.08 g dm/kg体重的II组，持续28天。安乐死后，收集大脑并使用常规组织学技术包埋在石蜡块中。使用过氧化物酶-抗过氧化物酶方法对额叶海马切片进行CR免疫组织化学染色。在光学显微镜下对CR免疫反应性（CR-IR）中间神经元进行形态学和形态计量学分析。结果显示，C组和I组动物大脑的两个区域中细胞的形状和分布相似。然而，在II组大鼠中偶尔观察到海马CA1区和DG中的CR-IR中间神经元。形态计量学研究结果显示，与C组相比，I组和II组受试脑区细胞的表面积和形状指数没有统计学上的显著差异。仅在II组大鼠中，发现DG中CR-IR中间神经元的数字免疫染色强度增加。在含有CAP的大剂量哈瓦那辣椒果实的影响下，海马CA1区和DG中CR-IR中间神经元数量较少，可能是由TRPV1受体的激活以及这些细胞中Ca2+离子的增加所致。这种现象最终可能导致神经元死亡，并可能干扰神经传导。
