The inhibitory action of corticotropin-releasing hormone on gonadotropin secretion in the ovariectomized rhesus monkey is not mediated by adrenocorticotropic hormone

Earlier observations in our laboratory indicated that i.v. infusion of human/rat corticotropin-releasing hormone (hCRH) suppresses pulsatile luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release in ovariectomized rhesus monkeys. Since cortisol secretion increased significantly as well, it was not possible to exclude the possibility that this inhibitory effect of hCRH on gonadotropins was related to the activation of the pituitary/adrenal axis. The purpose of the present study was to determine the role of pituitary/adrenal activation in the effect of hCRH on LH and FSH secretion. We compared the effects of 5-h i.v. infusions of hCRH (100 micrograms/h, n = 7) and of human adrenocorticotropic hormone (ACTH) (1-24) (5 micrograms/h, n = 3; 10 micrograms/h, n = 3, 20 micrograms/h, n = 3) to ovariectomized monkeys on LH, FSH, and cortisol secretion. As expected, during the 5-h ACTH infusions, cortisol levels increased by 176-215% of baseline control, an increase similar to that observed after CRH infusion (184%). However, in contrast to the inhibitory effect observed during the CRH infusion, LH and FSH continued to be released in a pulsatile fashion during the ACTH infusions, and no decreases in gonadotropin secretion were observed. The results indicated that increases in ACTH and cortisol did not affect LH and FSH secretion and allowed us to conclude that the rapid inhibitory effect of CRH on LH and FSH pulsatile release was not mediated by activation of the pituitary/adrenal axis.     

Combinations of palytoxin or 12-O-tetradecanoylphorbol-13-acetate and recombinant human insulin growth factor-I or insulin synergistically stimulate prostaglandin production in cultured rat liver cells and squirrel monkey aorta smooth muscle cells

In the presence of 12-O-tetradecanoylphorbol-13-acetate (TPA) or the non-TPA-type tumor promoter, palytoxin, recombinant human insulin growth factor-I (IGF-I) and insulin synergistically stimulate prostaglandin production in rat liver cells (the C-9 cell line). Combinations fo palytoxin or TPA with recombinant human IGF-I or insulin also synergistically stimulate deesterification of c ellular lipids in C-9 cells prelabelled with [³H]arachidonic acid. With both types of stimulations, prostaglandin production or deesterification, the synergistic response of the IGF-I and insulin is greater with palytoxin than with TPA. Production of prostaglandin E₂ and F_2α by squirrel monkey smooth muscle cells incubated in the presence of TPA and insulin also is greater than the sum of the effects taken independently.     

关于法氏囊内T细胞及腔淋巴细胞的研究

本实验表明,法氏囊内存在一个T淋巴细胞弥散渗透区(DIA),在初生雏鸡中开始形成,一月半发育完善,同样在ISE(滤泡间上皮)上皮层内亦存在少量的弥散T淋巴细胞,上述淋巴细胞与腔淋巴细胞,形态结构极为相似。酯酶活性反应均显示T细胞型。 另外初生雏鸡切除胸腺,不仅影响DIA的发育而且影响滤泡的发育。     

楝科物质对亚洲玉米螟幼虫取食和生长发育的影响

近年来植物成分对昆虫行为和生长发育的影响很受人们重视。对印楝(Azadirachta indica)的研究证明其含有多种杀虫物质(Schmutterer和Ascher等,1981)。国外报道与印楝为近缘种的苦楝(Melia azadirach)也对昆虫有拒食和干扰生长发育的作用(Schmutterer,1981;Tu和Rueda等,1981),并从中分离出了多种活性物质(Cox,1981)。我国也曾研究应用苦楝防治害虫(中国土农药志编辑委员会,1959),最近证明川楝(Melia toosendan)中成分对水稻三化螟有内吸致毒和拒食作用(赵善欢和张     

诱导茄链格孢菌分生孢子形成的新技术

本文报道诱导茄链格孢菌(Alternaria solani)分生孢子形成的一种新技术。生长在马铃薯-葡萄糖-琼脂(PDA)上两天的茄链格孢菌琼脂块移接到玉米培养基上,置于日光灯下照射,诱发分生孢子梗生长。然后,再放在18℃下黑暗培养。12小时后,在菌丝块表面有大量的分生孢子形成。成熟的茄链格孢菌分生孢子用蒸馏水洗脱。     

湖南土家族的体质特征

以20至69岁的湖南土家族人为观察测量对象,根据1392人(男896,女496)的身高,1038人(男668,女370)的头部测量,364人(男235,女129)的五官测量和观察结果,分析该民族的体质特征,并与国内其他民族相比较。     

担子菌多糖及羊脾RNA对肿瘤的抑制与有关组织中cAMP含量关系的探讨

本文讨论了对带瘤小鼠注射香菇多糖、松口蘑多糖和羊脾RNA后,活体内有关组织中cAMP含量与抑瘤率之间的关系。 结果表明,上述活性物质不仅增强了机体免疫活性,同时亦促使机体内脾、瘤等组织的cAMP增高,此种增高,与抑瘤率成正相关。