分类号:Q503文献标识码:A
文章编号:0529-1356(2000)01-69
IMMUNOHISTOCHEMICAL AND IN SITU HYBRIDIZATION
STUDIES OF 5-HT AND 5-HT RECEPTOR IN
DECIDUAL CELLS OF HUMAN PLACENTAE
PU Ruo-lei
(Department of Histology and Embryology,the Fourth Military Medical University,Xi'an 710032,China)
HUANG Wei-quan
(Department of Histology and Embryology,the Fourth Military Medical University,Xi'an 710032,China)
YAO Bin
(Department of Histology and Embryology,the Fourth Military Medical University,Xi'an 710032,China)
SUN Lan
(Department of Histology and Embryology,the Fourth Military Medical University,Xi'an 710032,China)
Abstract:ObjectiveTo study the localization and quantification of 5-hydroxytryptamine(5-HT)、(5-HT receptor)and 5-HT1A receptor mRNA in decidual cells of human placentae.MethodsImmunohistochemical methods, in situ hybridization methods and the technique of image analysis were used in the experiment.ResultsThe decidual cells of human placentae showed 5-HT and 5-HT receptor immunoreactivity,which were located in cytoplasm with negative nuclei.5-HT1A receptor mRNA hybridized signals was also detected in cytoplasm.The relative amount of 5-HT and its receptor varied with gestation ages and rose markedly with increasing week ages.ConclusionThe decidual cells of the human placenta may not only produce 5-HT but also be a 5-HT target organ.5-HT may play a self-modulation to the decidual cells.
Key words:5-hydroxytryptamine; 5-hydroxytryptamine receptor; 5-HT1A receptor mRNA; Decidual cell; Immunohistochemistry; In situ hybridization▲
人胎盘由来自胚胎的丛密绒毛膜和来自母体的基蜕膜两部分组成。先前的研究已经证明,人胎盘绒毛膜自身能合成5-羟色胺(5-HT)[1],又能表达5-HT的受体[2],说明胎盘绒毛膜产生的5-HT可通过自分泌或旁分泌途径,对胎盘起局部调节作用。但是胎盘的基蜕膜能否产生5-HT及其受体未见报道。本实验用免疫组织化学及原位杂交方法对该问题进行了研究。
材料和方法
1. 试剂
兔抗5-HT多克隆抗体[3]及兔抗5-HT抗β型独特型抗体[4]均为本室自制。ABC药盒为武汉博士德生物工程公司产品。地高辛标记的5-HT1A受体寡核苷酸探针由我校解剖学教研室提供。碱性磷酸酶标记的羊抗地高辛抗体Fab段(Akp-Anti-Dig-AbFab)为德国宝灵曼公司产品。RNase A为华美公司产品。
2. 材料
胎龄为6~10周、16、24、40周人胎盘各5例,由唐都医院妇产科提供。
3. 标本制备
取小块新鲜的胎盘组织,用4℃生理盐水洗去血液,入Bouin液固定过夜,石蜡包埋,制成6μm厚的石蜡切片,将各周龄胎盘石蜡切片贴在同一载玻片上,在37℃温箱烘干备用。另取小块胎盘组织经Bouin液固定后,入20%蔗糖液,待组织块下沉后,用恒冷箱切片机切成20μm厚的冰冻切片,将各周龄胎盘的冰冻切片贴在同一涂有明胶的载玻片上,置43℃温箱烘干24h备用。
4. 免疫组织化学反应程序
石蜡切片脱蜡水化后,入甲醇-H2O2孵育20min,除去内源性过氧化物酶,然而按ABC法进行5-HT、5-HT受体免疫组织化学反应。第一抗体分别为5-HT抗体(1∶5 000稀释)和5-HT抗独特型抗体(1∶200稀释),在4℃冰箱内孵育24h,生物素化羊抗兔IgG抗体(1∶100稀释)室温孵育1h,ABC复合物(1∶100稀释)室温下孵育30min。用正常兔血清分别取代第一抗体作阴性对照。
5. 原位杂交程序
胎盘组织冰冻切片在43℃温箱烘干后,依次入0.1mol/L PBS漂洗5min,0.1mol/L甘氨酸5min,0.3% Triton X-100 15 min,经蛋白酶K(1mg/L)孵育30min后,入4%多聚甲醛(用0.1mol/L PBS配制)5min,0.1mol/L PBS 5min ×2,入0.5%乙酸酐(用0.1mol/L三乙醇胺配制)10min,最后入2×SSC进行预处理10min后,滴加杂交液(含地高辛标记的5-HT1A受体寡核苷酸探针0.5μg/L,于43℃恒温箱中杂交12~16h。杂交后切片入4×SSC 20min,再入RNase A溶液(20mg/L)30min,以消化未杂交的探针。切片再依次经1×SSC,0.5×SSC和0.05×SSC各15min,滴加AkP-Anti-Dig-AbFab(1∶500稀释),置湿盒内于室温孵育5h,然后经0.05mol/L PBS洗5min×4,再经TSM1和TSM2液各10min,最后滴加NBT/BCIP混和液室温显色3~6h,入0.05mol/L PBS 5min终止显色反应。切片在37℃温箱烘干后,二甲苯透明,树胶封固。阴性对照试验分别用不含探针的杂交缓冲液取代含探针的杂交液,及用正常羊血清取代AkP-Anti-Dig-AbFab进行孵育。
6. 图像分析方法
用Q-500图像分析系统(美国Leica公司)对不同发育阶段胎盘蜕膜细胞的5-HT及其受体免疫反应产物的相对含量进行测定,在光镜下(×100)每例随机取样测5个视野,10个单位面积,每组共测50个单位面积,计算出每个单位面积的5-HT及其受体免疫反应产物的相对含量,用组间t检验方法作统计学处理。
结果
1. 免疫组织化学反应
5-HT及5-HT受体免疫反应性的细胞呈深棕色,背底呈浅黄色或不着色。对照为阴性反应。被检各周龄的胎盘均可观察到5-HT及5-HT受体免疫反应性细胞,细胞为梭形、卵圆形或多边形,成群分布。两种免疫反应阳性物质均分布于细胞质内,胞核为阴性(图1,2)。妊娠等6周的胎盘,5-HT及其受体免疫反应性的蜕膜细胞稀少,着色也较淡,随着妊娠周龄的增加,5-HT及其受体免疫反应性的蜕膜细胞数逐渐增加,着色也逐渐增强。
5-HT、5-HT受体及其mRNA在蜕膜细胞的定位
140周龄人胎盘5-HT免疫染色阳性的蜕膜细胞。×400
Immunohistochemical and in situ hybridized reaction for 5-HT and 5-HTR in developing decidual cells of human plancentae over the course of pregnancy:
Fig.1The decidual cells in 40 week placenta,showing 5-HT immunoreactivity.×400
图240周龄人胎盘5-HT受体免疫染色阳性的蜕膜细胞。×400
Fig.2The decidual cells in 40 week placenta,showing 5-HTR immunoreactivity.×400
2. 原位杂交
含5-HT1A受体mRNA杂交信号的细胞呈蓝色,背底无色,对照为阴性。被检各周龄的胎盘,均可观察到含5-HT1A受体mRNA杂交信号的蜕膜细胞,细胞的形态及分布特点与5-HT受体免疫染色细胞相似,5-HT1A受体mRNA的杂交信号定位于细胞质内(图3)。
图340周龄人胎盘含5-HT1A受体mRNA杂交信号的蜕膜细胞。×400
Fig.3The decidual cells in 40 week placenta,showing 5-HT1A receptor mRNA hybridized signal.×400
3. 免疫反应产物的定量分析
不同发育阶段人胎盘蜕膜细胞5-HT及其受体免疫反应产物图像分析结果见表1和表2。从表中可见,5-HT及其受
