摘要:

AbstractSevering the dorsal vessel (DV) behind the corpus allatum (CA), or in the anterior part of the abdomen ofRhodnius prolixus, greatly reduces egg production, an effect which is abolished by the topical application of juvenile hormone l (JH l). Severing the DV in the posterior abdomen does not result in a marked reduction of egg production, although severing the alary muscles in segments V and VI has a similar effect to severing the DV in the anterior abdomen. Reduced egg production caused by severing the DV on day 8 postemergence does not occur if the nerves connecting the CA to the brain are severed on day 1 post emergence. However, egg production is reduced if the DV is severed on day 1 post emergence and the connections between the brain and the CA severed on day 8, suggesting that inhibition of the CA caused by severance of the DV requires innervation from the brain. An isolated CA implanted into an animal decapitated immediately after feeding escapes from the inhibition imposed by severance of the DV. Conversely, the CA in an insect, the head of which has been decapitated just anterior to the CA, remains inhibited. This result suggests that the head posterior to the brain must be present to maintain inhibition. It is concluded that DV severance acts on the brain via some humoral influence to impose inhibition on the CA, and that an endocrine center in the head is required in order to maintain the inhibition.

ISSN:0739-4462    

DOI:10.1002/arch.940110302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThe stable fly hemolymph was analyzed after a blood meal. The hemolymph volume increased to approximately three times the pre‐feeding level 3–6 h after a blood meal and gradually returned to normal 18 h after the blood meal. The osmotic pressure decreased approximately 10% following a blood meal and gradually returned to normal with a pattern that was a mirror‐image of that of the hemolymph volume. Concentrations of cations and anions are not directly affected by the ingested blood, indicating a possible selective excretory mech

ISSN:0739-4462    

DOI:10.1002/arch.940110303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractWhole hemolymph from the American cockroach,Periplaneta americana, efficiently binds juvenile hormone (JH) III and to a lesser extent JH‐I and 10, 11‐epoxyfarnesyl diazoacetate (EFDA). The dissociation constants for racemic JH‐III and EFDA are 30 ± 2 nM and 1.0 μM, respectively. Isolated lipophorin also binds [3H]JH‐III and to a lesser extent JH‐I. Other proteins from the hemolymph do not bind JH‐III. Binding of JH‐III to lipophorin is enantioselective. The dissociation constant, measured with a 92% 10R and 8% 10S mixture, is 21 ± 2 nM. Each lipophorin molecule contains one specific binding site for JH‐III. It is concluded that lipophorin is the JH‐III‐specific transport protein in the hemolymph of the American cockroach. By a combination of photoaffinity labelling and gradient electrophoresis with sodium dodecyl sulphate on polyacrylamide gel, we showed that the JH‐III‐specific binding site is probably

ISSN:0739-4462    

DOI:10.1002/arch.940110304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThe hemolymph of diapausing larvae of the stem borer,Busseola fuscaFuller (Lepidoptera: Noctuidae), contains an electrophoretically distinct protein band on nondenaturing polyacrylamide gels. The protein, called the Busseola diapause protein (BDP), was purified by a combination of density gradient ultracentrifugation, gel permeation, and affinity chromatography. It is a high molecular weight protein (Mr∼5 × 105; pl = 6.1) that is composed of two subunits, I (Mr∼88,000 ± 4,000) and II (Mr∼79,000 ± 1,000), which are not linked by disulfide bridges. The protein contains both lipids (2%) as well as covalently bound carbohydrates (1%). The inability to stain the fluorescein isothiocyanate‐conjugated concanavalin A (FITC‐Con A) suggests that the carbohydrate moiety of BDP is not of the high mannose type. Amino acid analysis showed a high tyrosine plus phenylalanine content (16 mol%). Labeling studies using [35S]‐methionine showed that de novo synthesis by the fat body tissue occurs only in diapausing larval insects. It is proposed that the BDP could serve a storage function by providing the amino acids needed for the synthesis of pupal and ad

ISSN:0739-4462    

DOI:10.1002/arch.940110305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

摘要:

AbstractThe roles of grouping and mating in modulating the activity of the corpora allata (CA) in adult female cockroaches were investigated using the in vitro radiochemical assay of juvenile hormone (JH) biosynthesis. Isolated virgin females have longer, asynchronous cycles of CA activity and oocyte maturation than do isolated females mated on day 8. Three factors were identified as the major contributors to this difference: (1) an experimental artifact of selection for sexually receptive females, (2) a positive effect of grouping on JH synthesis and oocyte maturation, and (3) a positive effect of copulation on oviposition and retention of the ootheca. Mated females constitute a subpopulation of receptive females that differ significantly from other females by having higher rates of JH synthesis prior to mating. The relative importance of such selection is substantial when the rate of mating is low, as in experiments with isolated females that are exposed to males for a short period of time. Long‐term exposure of females to males introduces a grouping effect, which obscures any additional effect of mating on CA activity and oocyte development. However, mating influences ootheca formation and its retention. The effect of grouping can be mimicked in isolated females by transection of the nerves connecting the CA–corpora cardiaca complex to the brain, suggesting that in this insect isolation causes brain inhibition of the CA, and grouping provides disinhibitory stimuli that release the CA from brain inhibit

ISSN:0739-4462    

DOI:10.1002/arch.940110306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0739-4462    

DOI:10.1002/arch.940110307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY

ISSN:0739-4462    

DOI:10.1002/arch.940110301

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1989

数据来源: WILEY