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  • 1
    Electronic Resource
    Electronic Resource
    Juvenile hormone titre and regulation in the cockroachDiploptera punctata (1985)
    Springer
    Cellular and molecular life sciences 41 (1985), S. 1028-1034 
    Details
    ISSN: 1420-9071
    Keywords: Cockroach ; Diploptera punctata ; juvenile hormone titre ; juvenile hormone half-life ; juvenile hormone release rate ; gonotrophic cycle ; allatectomy ; nonhemolymph juvenile hormone pool
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Titres of juvenile hormone (JH) have been determined in both hemolymph and whole body extracts of femaleDiploptera punctata during the first gonotrophic cycle using a method employing gas chromatography/mass spectrometry for qualitative and quantitative analysis. JH III is the sole JH found in both adult and last instarD. punctata. Maximum values of ∼ 1500 ng/ml (∼6μM) were observed at the middle of the gonotrophic cycle, when basal oocyte growth rate was greatest. Changes in rates of JH release in vitro by corpora allata paralleled closely the changes in JH titre, suggesting that biosynthesis is a major regulator of titre. JH levels per animal were calculated from observed JH titres, and at certain time points in the gonotrophic cycle JH levels obtained from analysis of whole bodies were significantly greater than those predicted from hemolymph titres. These results suggest the existence of a nonhemolymph JH pool inD. punctata. Decay in JH titre after allatectomy of 5 day females has also been studied. Following a rapid initial decline, the rate of decay slowed appreciably 4 h post-operation. Thus, use of a first-order rate constant to estimate half-life of JH significantly underestimated the longevity of the hormone. The apparent persistence of JH following allatectomy may be due to the existence of a nonhemolymph JH pool.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01952127
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  • 2
    Electronic Resource
    Electronic Resource
    Identification of JH III as the princpal juvenile hormone inLocusta migratoria (1981)
    Springer
    Cellular and molecular life sciences 37 (1981), S. 909-910 
    Details
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary JH titers in the hemolymph of nymphal and adult femaleLocusta migratoria migratorioides (R. and F.) were determined using a selective mass spectrosc opic detection technique. Only JH III could be found in either stage, with no detectable JH I (or II). Titers observed were 10–1000-fold lower than those found via a recently reported radioimmunoassay procedure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01985709
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  • 3
    Electronic Resource
    Electronic Resource
    Titers of ecdysone, 20-hydroxyecdysone and juvenile hormone III throughout the life cycle of a hemimetabolous insect, the ovoviviparous cockroachNauphoeta cinerea (1985)
    Springer
    Cellular and molecular life sciences 41 (1985), S. 913-917 
    Details
    ISSN: 1420-9071
    Keywords: Ecdysteroids ; juvenile hormone III ; developmental changes ; cockroach ; Nauphoeta cinerea
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Titers of ecdysone, 20-hydroxyecdysone and juvenile hormone III were measured in whole body extracts or hemolymph of embryos, first, penultimate and last stadium nymphs, and adult females ofNaupoheta cinerea. We used a gas-chromatography/mass spectrometry method for quantifying juvenile hormone and a radio-immunoassay for ecdysteroid determination. Juvenile hormone III is particularly abundant in the embryonic stage (up to 960 ng/g), at a low level in first and penultimate stadium nymphs (2–10 ng/ml) and almost absent in the last nymphal stadium; in the adult female the juvenile hormone titer rises to 180 ng/ml in hemolymph during rapid oocyte growth. The titers of ecdysone and 20-hydroxyecdysone undergo similar fluctuations in the embryonic and nymphal stages, being highest at the time of cuticle formation in the embryo and a few days before the nymphal and adult molts (around 100–200 ng/ml for exdysone and 2–4 μg/ml for 20-hydroxyecdysone).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01970010
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    Paper (German National Licenses)
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  • 4
    Electronic Resource
    Electronic Resource
    Juvenile hormone catabolism inManduca sexta: Homologue selectivity of catabolism and identification of a diol-phosphate conjugate as a major end product (1993)
    Springer
    Cellular and molecular life sciences 49 (1993), S. 988-994 
    Details
    ISSN: 1420-9071
    Keywords: Juvenile hormone esterase ; juvenile hormone epoxide hydrolase ; juvenile hormone binding protein ; reversed-phase liquid chromatography assay
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract We studied time-dependent metabolism of (10R)-[3H] juvenile hormone (JH) III and (10R, 11S)-[3H]JH I injected intoManduca sexta larvae; the hormones are metabolized to polar metabolites, expecially the JH acid-diol, and an unknown. Products were analyzed using a reversed-phase liquid chromatography assay. (10R)-JH III is metabolized much more rapidly than (10R, 11S)-[3H]JH I, whether injected seperately or as a mixture of hormones. The unknown metabolites of JH I and JH III were identified as phosphate conjugates of JH I and JH III diol by tandem mass spectral analysis of isolated samples. The phosphate conjugate of JH I diol is the principle end product of JH I metabolism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02125646
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