To investigate physiological roles of basal levels of circulating LH on follicular development during the second half of pregnancy in golden hamsters, we treated animals with anti-luteinizing hormone (A/LH) or normal horse serum (control serum) at 1100 h on day 12 of pregnancy (day 0 of pregnancy=sperm positive in vaginal smear). Thereafter, changes in plasma concentrations of immunoreactive (ir)-inhibin, estradiol-17β, progesterone and testosterone were determined until 48 h after the treatment; ovaries were also examined immunohistochemically. Furthermore, pregnant golden hamsters were injected with human chorionic gonadotropin (hCG) to determine the effects of immunoneutralization of LH on follicular activity. Plasma concentrations of ir-inhibin and estradiol-17β decreased significantly within 24 h after A/LH treatment, while plasma concentrations of progesterone and testosterone were unchanged. The number of follicles ovulating in response to hCG in the A/LH treated groups (7.0 ± 3.4, n=3) was significantly lower than in the control serum treated group (34.6 ± 4.8, n=5) at 24 h after the treatment. Immunostaining of inhibin α subunit was observed in granulosa cells of healthy and atretic large follicles at 24 h after A/LH treatment, whereas immunopositive reaction of aromatase was not observed in atretic follicles. Positive immunoreaction of 17α-hydroxylase/C17, 20-lyase (CYP17) was observed in theca cells of healthy follicles but not in atretic follicles. These results clearly demonstrate that basal levels of circulating LH are important for maturation of antral follicles and secretion of ir-inhibin and estradiol-17β, but not for progesterone during the second half of pregnancy in the golden hamster.
The orangutan population and habitat variability analysis (PHVA) workshop stated that the population and the distribution of orangutans decreased very much over the past 20 years. The author has studied the ecology of orangutans in Kutai national park, East Kalimantan, Indonesia since 1983. The situation of orangutans has changed since the great forest fires and droughts and the coal mine operation. The distribution of orangutans in East Kalimantan is reported and status and the future plans for conservation of orangutans are discussed in this paper.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPlatinum(0)-catalyzed diboration of alkynesTatsuo Ishiyama, Nobuo Matsuda, Norio Miyaura, and Akira SuzukiCite this: J. Am. Chem. Soc. 1993, 115, 23, 11018–11019Publication Date (Print):November 1, 1993Publication History Published online1 May 2002Published inissue 1 November 1993https://pubs.acs.org/doi/10.1021/ja00076a081https://doi.org/10.1021/ja00076a081research-articleACS PublicationsRequest reuse permissionsArticle Views4454Altmetric-Citations392LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (2)»Supporting Information Supporting Information Get e-Alerts
Abstract Treatment of 1-bromo-1-alkenyldialkylboranes with lead(IV) acetate or iodosobenzene diacetate afforded 1-bromo-1,2-dialkylethylenes in moderate yields. Furthermore, both E-isomers and Z-isomers could be independently obtained as the main products by the use of different reaction conditions.
