钕在小鼠体内的分布与蓄积及对孕酮分泌的影响

应用核素示踪方法研究147Nd在小鼠体内的分布、蓄积及其对孕酮分泌的影响.一次性腹腔注射200mg@kg-1147Nd在各组织中呈不均匀分布,骨骼中表现出了高度蓄积性,且随时间的延长而增加;在眼睛、血液和大脑中均有一定的蓄积,但因排泄和体内再分配随时间而呈下降趋势;在Nd处理后血清中孕酮浓度显著低于对照组,表现了明显的抑制作用.     

[~3H] TYROSINE BINDING TO PLASMA MEMBRANE PREPARATION OF RAT CORPORA LUTEA

Plasma membrane preparations of rat corpora lutea have been incubated with [~3H]tyrosine. [~3H]-tyrosine binding sites are demonstrated and Scatchard analysis shows that there exist two types of binding sites, one with high affinity and low capacity, the other with low affinity and high capacity. The kinetics studies demonstrate that the [~3H]tyrosine binding to the two types of binding sites is reversible and the speed of binding to the high affinity type is faster than that to the low affinity type. The analysis of the chemical structure of tyrosine analogues and related compounds with respect to the specificity of the binding sites reveal that both types of binding sites show specificity, but the specificity of the high affinity sites is higher than that of the low affinity sites. The relations of tyrosine structure to binding processing and to tyrosine inhibitory action on hCG-induced progesterone production are discussed. It is suggested that the high affinity binding sites might be regarded as "ty     

Mechanism and kinetics for scavenging superoxide anion by progesterone

The chemical reaction of progesterone with superoxide anion O^.-₂ in 0.1 mol/L NaHCO₃ medium is studied by polarography. Differing from the indirect inhibition of O^.-₂ generation by synthesized glucocorticoids in mechanism, the function that progesterone scavenges O^.-₂ is ascribed to that O^.-₂ directly oxidizes the C == C double bond conjugated with the carbonyl moiety of progesterone molecule to a free radical, and then is reduced to H₂O₂. The result obtained in this work gives new evidence for biomedical research. The equation of rate constant of the oxidization reaction is deduced, and the apparent rate constant obtained is 308 L·mol^-1·s^-1.     

不同机制参与黄体酮扩张兔血管作用

用离体血管条灌流实验方法 ,观察黄体酮对血管条去甲肾上腺素 (NA) ,Ca Cl2 ,KCl反应的影响 ,并观察给予 L- NNA、甲烯蓝 (MB)、吲哚美辛、普萘洛尔及去除内皮细胞后 ,黄体酮扩张血管作用的变化 .结果发现 :黄体酮 10 -4 mol· L-1及 10 -5mol· L-1分别使 NA和无 Ca2 +高 K+Krebs液中 Ca Cl2 量效曲线明显右移 ,最大反应压低 ,PD2 ′分别为 3.51和 4 .56 .黄体酮 2 .5× 10 -4mol· L-1使无 Ca2 + 液中 NA10 -6mol· L-1收缩血管作用明显减弱 (p <0 .0 0 1) ,但不影响 Ca Cl210 mmol· L-1引起的收缩 .L - NNA,MB及去除内皮可明显减弱黄体酮扩张 KCl 4 0 mmol· L-1的收缩血管作用 ,但吲哚美辛和普萘洛尔无明显影响 .结果表明 :黄体酮可通过受体操纵 Ca2 + 通道抑制 IP3 途径引起的内 Ca2 + 释放 ,也可通过电压依赖式 Ca2 + 通道抑制外 Ca2 + 内流 ,使血管条舒张 ,其作用有内皮依赖性 ,部分与 NO和 c GMP有关     

SOME FACTORS AFFECTING [~3H]TYROSINE BINDING TO PLASMA MEMBRANE PREPARATION OF RAT CORPORA LUTEA in vitro

Temperature, pH, enzymes and ions affected the two types of [~3H]tyrosine binding sites differently. The optimal temperature and pH for the high affinity sites were 24 C and 7.4, and for the low affinity sites 37℃ and 7.0, respectively. The [~3H]tyrosine binding to the high and low affinity sites was not observed at 55℃, nor at pH 6.0 or pH 8.5. Trypsin reduced [~3H]tyrosine binding to the high affinity sites, but had no effect on the binding to the low affinity sites. Neuraminidase reduced [~3H]tyrosine binding to the low affinity sites, but had no effect on the binding to the high affinity sites. None of cycloheximide, kCG, cAMP, and progesterone affected [~3H]tyrosine binding.     

中国美利奴军垦绵羊发情周期血液中促黄体激素,孕酮变化的研究

本实验用放射免疫测定法测定了中国美利奴军垦型绵羊(8只)发情期血液中促黄体激素(LH),孕酮含量及其变化。LH含量在黄体期为4.9±0.31μg/l;发情开始后约6～12h其含量达到53.2±0.11μg/l。孕酮含量在黄体期最高值为2.4±0.21μg/l;在发情开始到第3天含量为0.39±0.21μg/l。     

孕酮对小鼠不同脑区和卵巢、子宫中[~3H]-GABA 与 GABA_A 受体结合的影响

采用放射配体受体结合分析的方法，研究了小鼠大脑皮层、小脑、海马、下丘脑四个脑区和卵巢、子宫中孕酮对外源性［３Ｈ］－ＧＡＢＡ与ＧＡＢＡＡ受体结合的影响，结果表明：１）孕酮使中枢四个脑区和子宫中外源性［３Ｈ］－ＧＡＢＡ的结合量显著下降；２）ＧＡＢＡＡ受体拮抗剂Ｐｉｃｒｏ－ｔｏｘｉｎ与孕酮＋Ｐｉｃｒｏｔｏｘｉｎ对［３Ｈ］－ＧＡＢＡ结合的影响无明显差别；３）在卵巢中孕酮对［３Ｈ］－ＧＡＢＡ与ＧＡＢＡＡ受体的结合无明显影响。这表明中枢和子宫存在的孕酮，能降低ＧＡＢＡＡ受体对外源性［３Ｈ］－ＧＡＢＡ的结合，而且可被Ｐｉｃｒｏｔｏｘｉｎ所拮抗，提示孕酮可能通过影响ＧＡＢＡＡ的功能，发挥巴比妥样效应，并且其作用位点可能与Ｐｉｃｒｏｔｏｘｉｎ的位点靠近。     

Synthesis of 19-substituted steroids of the 16α,17α-cyclohexanopregnane series and study of their interactions with rat uterine cytosol and blood serum proteins

New 16α,17α-cyclohexanopregnanes (pregna-D′₆-pentaranes) containing alkyl or heteroatomic substituents in position 19, namely, 19-methylidene-, 19-methyl-, 19-methoxyimino-, and 19-(3-methoxycarbonylpropoxyimino)-16α,17α-cyclohexanopregn-4-ene-3,20-diones were synthesized, and their interactions with the progesterone receptor and pentarane-binding proteins of rat uterus cytosol and rat blood serum was studied. The same substituent in position 19 of the steroid molecule can affect in opposite direction its affinity to these proteins. These results suggest differences in the structures of the ligand-binding pockets of the three proteins in the region surrounding the C(10) atom of the steroid nucleus. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2579–2584, November, 2005.     

扶桑花石油醚提取物HR-1对体外培养的人早期胎盘绒毛组织分泌功能的影响(1)

扶桑（ＨｉｂｉｓｃｕｓｒｏｓａｓｉｎｅｎｓｉｓＬ．）花石油醚提取物ＨＲ－１对体外培养的人早期胎盘绒毛组织分泌功能的影响．实验结果表明：ＨＲ－１对人早期胎盘绒毛组织ＨＣＧ和孕酮的分泌、对绒毛滋养层细胞的生长均有较强的抑制作用