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221.
222.
Abstract. The regulation of Juvenile Hormone (JH) HI biosynthesis and release by the corpora allata (CA) was studied in final instar male and female larvae of the earwig, Euborellia annulipes , using a radiochemical assay in vitro. In males, maximal biosyntiiesis of JH IH occurred on day 1, then declined to virtually undetectable levels for the following 12 days of the stadium, and finally increased on days 14–16. In females, peaks of biosynthesis were detected on days 0–1 and on day 12. A further investigation of the 12-day-old larvae demonstrated mat in nonmoulting males and females, JH UJ biosynthesis was undetectable. However, for males and females undergoing ecdysis, the biosynthesis of JH III was detected and quantified.
The addition of 60 μM farnesoic acid to the incubation medium significantly increased the production of JH III by CA taken from females from day 8 until the end of the stadium. Glands from 12-day old females that had initiated ecdysis were stimulated by farnesoic acid. By contrast, we could detect no stimulation of production of JH III by farnesoic acid in CA taken from males, even very late in the stadium. CA from newly emerged adult males and females were more active than those of larvae, and were greatly stimulated by farnesoic acid. CA from females immediately after emergence were stimulated significantly more by farnesoic acid man were glands from newly emerged males. These results suggest fundamental differences in the synmetic activity of CA for males and females in this insect. 相似文献
The addition of 60 μM farnesoic acid to the incubation medium significantly increased the production of JH III by CA taken from females from day 8 until the end of the stadium. Glands from 12-day old females that had initiated ecdysis were stimulated by farnesoic acid. By contrast, we could detect no stimulation of production of JH III by farnesoic acid in CA taken from males, even very late in the stadium. CA from newly emerged adult males and females were more active than those of larvae, and were greatly stimulated by farnesoic acid. CA from females immediately after emergence were stimulated significantly more by farnesoic acid man were glands from newly emerged males. These results suggest fundamental differences in the synmetic activity of CA for males and females in this insect. 相似文献
223.
S. Setrakian B. Oliveros-Saunders S. V. Nicosia 《In vitro cellular & developmental biology. Animal》1993,29(11):879-883
Summary Ovarian (OM) and extraovarian (EM) mesothelia represent a common source of gynecologic malignancies with yet unclear pathogenesis.
Ovulation triggers a finite wave of DNA synthesis and morphogenesis only in native OM cells, probably through the activation
of intraovarian growth factors. To evaluate their growth response to such factors, OM and EM cells were obtained from estrous
New Zealand white rabbits by enzymatic dispersion and unit gravity sedimentation. Cell cultures were maintained in serumless,
fibronectin-rich, HL-1 medium without or with rabbit corpora lutea tissue extracts (CLE). The growth effects of CLE were evaluated
by measuring percent changes in cell number relative to controls (CCN), cell population doublings (CPD), cell population doubling
time in hours (CPDT). After 7.5 days, CLE enhanced (P<0.001) the growth of both OM and EM cells, which exhibited, respectively, a CCN of 214 and 257%; a CPD of 2.89 and 2.87;
and a CPDT of 54.39 and 59.49. CLE-treated OM and EM cells were smaller, formed more cohesive monolayers, and exhibited more
frequent and diffuse microvilli than control cells. These data show a similar in vitro response of OM and EM cells to luteal
growth factors, suggesting that the lack of postovulatory morphogenesis in native extraovarian mesothelia is due to the spatially
restricted activity of intraovarian growth factors. 相似文献
224.
参照我室Wang Xiao-Ning的黄体细胞制备方法,制成大鼠黄体细胞悬浮液,经蔗糖密度梯度离心分离大,小黄体细胞,经60min预培灌后,每10min收集一次培灌液,用RIA测定其中孕酮含量,实验结果表明,在培灌系统中,大黄体细胞的基础孕酮分泌量明显高于小黄体细胞,但小黄体地hCG的敏感性强于大黄体细胞,不同剂量的酪氨酸对hCG致大,小黄体细胞孕酮生成有不同程度的抑制,对小黄体细胞的抑制作用较为 相似文献