Fazekas I, Bácsy E, Varga I, Slowik F, Bálint K, Pásztor E, Czirják S, Gláz E
National Institute of Neurosurgery, Budapest, Hungary.
Folia Histochem Cytobiol. 2000;38(3):119-27.
Six GH adenomas and three prolactinomas were investigated by light- and electron-microscopic morphological and immunocytochemical methods and the effect of vasoactive intestinal polypeptide (VIP) on growth hormone (GH) and prolactin (PRL) secretion was tested in vitro. The tumour cells of the acromegalic patients revealed both GH and PRL immunoreactivity while prolactinomas showed only PRL activity. All the adenomas stained immunocytochemically also for VIP. By electron microscopy, the tumours included two densely and two sparsely granulated GH, two mixed GH/PRL, and three sparsely granulated PRL adenomas. The dissociated cells were explanted, and cultured in vitro. The cultures in micro test plates were treated with VIP at different concentrations between 10(-5)-10(-12) M. GH and PRL contents in the culture media were measured by radioimmunoassay. GH release was significantly stimulated by VIP in a dose-dependent manner over the whole concentration range, while VIP was effective on the PRL release only at 10(-6)-10(-7) M concentration. The cells of a mixed adenoma were grown in Petri dishes and used for ultrastructural and immunocytochemical studies. The cytoplasmic structure of the cells treated with VIP corresponded to that of active hormone-secreting cells with large ergastoplasmic fields and Golgi zones containing secretory granules. Massive exocytotic events were encountered mainly in the GH-type cells. GH and PRL double immunocytochemistry showed the predominance of GH cells, many of them containing low amounts of PRL as well. Cells predominantly containing PRL were spread among them, they also might contain GH as well. Some of the cells contained only a single immunoreactive hormone. The intensity of gold labelling of the secretory granules appeared higher in the VIP-treated cells than in the untreated control ones which showed a cytoplasmic structure characteristic of glandular cells with low secretory activity. As all the adenoma cells both contained and reacted to VIP, our results are in agreement with an autocrine or paracrine effect of this peptide. The fine structure of the cells in the cultures treated with VIP supply an additional argument to the assumption that VIP may serve as a growth factor for these cell types.
采用光镜、电镜形态学及免疫细胞化学方法对6例生长激素腺瘤和3例催乳素腺瘤进行研究，并在体外检测血管活性肠肽（VIP）对生长激素（GH）和催乳素（PRL）分泌的影响。肢端肥大症患者的肿瘤细胞同时显示GH和PRL免疫反应性，而催乳素瘤仅显示PRL活性。所有腺瘤免疫细胞化学染色也显示对VIP呈阳性。电镜下，肿瘤包括2例密集颗粒型和2例稀疏颗粒型GH腺瘤、2例混合性GH/PRL腺瘤以及3例稀疏颗粒型PRL腺瘤。将解离的细胞进行体外培养。在微量试验板中培养的细胞用浓度在10⁻⁵ - 10⁻¹² M之间的不同浓度VIP处理。通过放射免疫测定法测量培养基中GH和PRL的含量。在整个浓度范围内，VIP均以剂量依赖性方式显著刺激GH释放，而VIP仅在10⁻⁶ - 10⁻⁷ M浓度时对PRL释放有效。将混合性腺瘤的细胞培养在培养皿中，用于超微结构和免疫细胞化学研究。用VIP处理的细胞的细胞质结构与具有大的内质网区域和含有分泌颗粒的高尔基体区域的活跃激素分泌细胞的结构相对应。大量胞吐事件主要见于GH型细胞。GH和PRL双重免疫细胞化学显示GH细胞占优势，其中许多细胞也含有少量PRL。主要含PRL的细胞散布于其中，它们也可能含有GH。一些细胞仅含有单一免疫反应性激素。与未处理的对照细胞相比，VIP处理的细胞中分泌颗粒的金标记强度更高，未处理的对照细胞显示出具有低分泌活性的腺细胞的细胞质结构特征。由于所有腺瘤细胞均含有VIP并对其产生反应，我们的结果与该肽的自分泌或旁分泌作用一致。用VIP处理的培养细胞的精细结构为VIP可能作为这些细胞类型的生长因子这一假设提供了额外的证据。
