MECHANISM OF CLEFT-PALATOGENESIS BY SECALONIC ACID D

癸二酸D的裂腭发育机制

基本信息

批准号：
3437706
负责人：
CHADA S REDDY
金额：
$ 10.31万
依托单位：
UNIVERSITY OF MISSOURI-COLUMBIA
依托单位国家：
美国
项目类别：
财政年份：
1989
资助国家：
美国
起止时间：
1989-05-01 至 1993-04-30
项目状态：
已结题

项目摘要

The objectives of these studies are to establish the biochemical basis for the pathogenesis of cleft palate in mice by the mycotoxin, secalonic acid D (SAD); and to confirm the(se) mechanism(s) by demonstrating a reversal of such biochemical effects(s) by the antiteratogenic agent, dimethylsulfoxide (DMSO). Timed-pregnant CD-l mice will be exposed to 30 mg/kg of SAD, intraperitoneally, in 5% (w/v) sodium bicarbonate (SB) or a 20% solution of DMSO in SB. Fetal palates collected between days 13.5 and 15.5 of development will be subjected to: 1) mitochondrial isolation to study palatal cellular respiration using an oxygen electrode, 2) isolation of plasma membranes to assess total and quabain sensitive (Na -K+) ATP-ase activities, 3) quantitation of palatal adenosine triphosphate and guanosine triphosphate levels using high performance ion-pai chromatography, 4) measurement of membrane phospholipase A2 activity using release of (1-14C) oleic acid from exogenous (1-14C) dioleoylphosphatidylcholine by palate homogenates, 5) assay of cyclooxygenase pathway enzyme activity by monitoring the conversion of exogenous C-arachidonic acid by palatal slices and homogenates into prostaglandins, 6) adenylate and guanylate cyclase assay of tissue homogenates, and 7) measurement of phosphodiesterase activity in palatal homogenates. These studies test the hypotheses that SAD-induced alterations in palatal cellular energy metabolism, prostaglandin synthesis, cyclase (adenylate and guanylate) activities, and/or phosphodiesterase activity could lead to previously observed changes in palatal cyclic nucleotide patterns and ultimately cleft palate by SAD, and that DMSO prevents the teratogenic effect of SAD by normalizing these SAD-induced changes. The results of these studies would not only indicate, in vivo, the relative importance of mechanisms (for e.g., prostaglandin synthesis) previously shown to be affected in vitro by other teratogens but also establish certain new biochemical events of normal palatogenesis (for e.g. guanylate cyclase and cGMP-phosphodiesterase) and indicate the importance of all of these pathways in SAD-induced cleft palate. This would lead to a greater understanding of the pathogenesis of environmentally caused cleft palate and may suggest preventive approaches to this common human malformation.

这些研究的目的是建立生化小鼠裂口发病的基础霉菌毒素，Scalonic Acid D（SAD）；并确认（SE）通过证明这种生化的逆转机制抗催化剂二甲基硫氧化物（DMSO）的作用。定时怀孕的CD-L小鼠将暴露于30 mg/kg的SAD，腹膜内，在5％（w/v）碳酸氢钠（SB）或20％中 DMSO在SB中的溶液。在13.5天之间收集的胎儿口味开发的15.5将受到：1）线粒体分离使用氧气研究子宫细胞呼吸电极，2）分离质膜以评估总和 Quabain敏感（Na -K+）ATP -ase活动，3）定量 palatal腺苷三磷酸和三磷酸鸟嘌呤水平使用高性能离子色谱法，4）测量膜磷脂酶A2活性使用（1-14C）油酸的释放来自外源（1-14c）二烯酰磷脂酰胆碱的酸的酸匀浆，5）测定环氧合酶途径的酶活性通过监测外源C-芳香酚的转化 palatal切片和匀浆成前列腺素，6）腺苷酸盐和组织匀浆的鸟苷酸环化酶测定，以及7）测量子宫匀浆中磷酸二酯酶活性。这些研究检验了悲伤引起的改变的假设 palatal细胞能量代谢，前列腺素合成，环化酶（腺苷酸盐和鸟苷酸盐）的活性和/或磷酸二酯酶活性可能导致先前观察到 pallatal循环核苷酸模式的变化和最终的裂口 SAD的口感，DMSO阻止了SAD的致畸作用通过标准化这些悲伤引起的变化。这些结果研究不仅表明体内相对重要先前显示的机制（例如前列腺素合成）受到其他畸胎系的体外影响，但也建立正常古质发生的某些新的生化事件（例如鸟苷酸环化酶和CGMP-磷酸二酯酶），并指示所有这些途径在悲伤引起的cle裂中的重要性。这将导致对环境引起的a裂，可能暗示预防性解决这种常见的人类畸形。