大斑芫菁滞育幼虫在滞育不同阶段体内糖类和醇类含量的变化

在以卵滞育的昆虫中昆虫滞育时的生理代谢特点已经得到了大量研究。本文对以末龄幼虫（5龄）滞育的大斑芫菁Mylabris phalerate（Pallas）在不同滞育阶段体内糖类和醇类代谢的特征进行了研究。结果表明： 滞育个体血淋巴中的海藻糖含量高于非滞育个体,且随滞育时间的加大逐渐升高,滞育5个月时达到最大值,为5.61 μmol/mL。糖原的含量随滞育的进程逐渐减少,滞育初期（0.5个月）为0.72 mg/mL,到滞育末期（5个月）时仅为0.1 mg/mL。滞育个体脂肪体中的海藻糖含量都高于非滞育个体,滞育1个月时为非滞育个体的3倍,至滞育末期时达非滞育个体的5倍,为2.5 μmol/g脂肪体。糖原含量总体变化趋势是随滞育时间的加大逐渐减少,滞育早期和中期都高于非滞育个体。在滞育过程中血淋巴积累的小分子多元醇主要为甘油,其次是山梨醇;而在脂肪体中主要为甘油,其次是甘露醇,少量积累山梨醇：表明大斑芫菁滞育幼虫主要积累的是海藻糖和一些小分子多元醇。滞育幼虫在准备滞育时储备了大量糖原,这些糖原可能为滞育期间海藻糖、山梨醇和甘油的代谢提供了原料。     

Carbohydrate and lipid metabolism during the last larval moult of the tobacco hornworm, Manduca sexta

Abstract. At 25°C and with a light regime of 17 h light and 7h dark, the last larval moult of the tobacco hornworm, Manduca sexta , lasts approximately 32 h, during which profound changes of metabolism were observed. At the onset of the moult, which coincides with the cessation of feeding, the proportion of active fat body glycogen phosphorylase increased from 10 (-2h) to 25–30% (Oh). A biphasic pattern with peak activities of 45–50% after t – 12 h and again just prior to the shedding of the cuticle (32 h) was subsequently observed. Haemolymph trehalose concentration decreased significantly from c. 35 (Oh) to 20mM (8h), but then recovered to an intermediate level (30mM; 12h). After completion of the moult, the trehalose concentration was 35–40 mM. The haemolymph glucose level in feeding fourth instar larvae was 4–5 mM, but decreased sharply before the onset of the moult to c. 1 mM, followed by a slow 6-fold increase over the next 20h. Prior to the shedding of the cuticle, the glucose level dropped again dramatically. The haemolymph lipid level increased slowly from an initial level of 1.2–1.4mg/ml during the early part of the moult, reaching a maximum of 1.8mg/ml after /= 16 h. Afterwards, a decrease of c. 50% was observed until ecdysis occurred. Oxygen consumption per animal decreased steadily from 30–35 μl/min pre-moult by approximately 70% to c. 10 μl/min but started to increase about 5 h before the animals resumed feeding.     

Trehalose turnover and the coexistence of trehalose and active trehalase in cockroach haemolymph

In the cockroaches Periplaneta americana, Periplaneta australasiae, Leucophaea maderae, and Nauphoeta cinerea, undiluted haemolymph, undiluted haemolymph to which 10% solid trehalose was added, and haemolymph diluted 100 or more times with 1% trehalose solution showed approximately equal trehalase activities (3 to 8 mg/ml per hr). No evidence for the presence of a trehalase inhibitor was found.Freshly drawn haemolymph of Periplaneta americana contained 14 to 16 mg trehalose/ml, which on standing was hydrolyzed to glucose at a rate of 4 to 8 mg/ml per hr. In this cockroach, the rate of haemolymph trehalose turnover was only 1.3 mg/ml per hr. This means that in vitro trehalose is hydrolyzed by undiluted haemolymph at several times the rate at which it is replaced in the haemolymph of the intact insect. The mechanism through which trehalose and trehalase can coexist in the haemolymph of the intact cockroach remains therefore unexplained.     

The biochemical effects of potassium chloride on the silkworm, （ Bombyx mori L.）

The supplementation with 50, 100 and 150μg/mL potassium chloride to the fifth instar larvae of the silkworm Bombyx mori on fat body glycogen, protein, total lipids and haemolymph protein and trehalose were analyzed. The fat body glycogen and protein and haemolymph protein were increased significantly in all the treated groups; whereas fat body total lipids increased only in 100 and 150μg/mL and haemolymph trehalose increased only in 150μg/mL potassium chloride-treated groups when compared with those of the corresponding parameters of the carrier controls.     

中红侧沟茧蜂寄生对寄主粘虫血淋巴糖类、脂类和蛋白质含量的影响

为揭示寄生蜂寄生对其寄主的生理调控机制, 室内对中红侧沟茧蜂Microplitis mediator寄生与未被寄生寄主粘虫Mythimna separata幼虫血淋巴中糖类、脂类和蛋白含量变化进行了测定。结果显示: 在滞育与非滞育条件下, 被寄生的粘虫血淋巴中糖原浓度均比未被寄生的粘虫高。滞育条件下寄生后12 d差异显著（P<0.05）, 被寄生粘虫糖原含量为7.93 μg/mL, 未被寄生粘虫糖原含量为4.70 μg/mL; 非滞育条件下寄生后6 d差异显著（P<0.05）, 被寄生粘虫糖原含量为14.35 μg/mL, 未被寄生粘虫糖原含量为5.47 μg/mL。海藻糖含量测定结果显示, 在滞育条件下寄生蜂对被寄生粘虫无明显影响, 而非滞育条件下影响效果差异显著（P<0.05）, 寄生后4 d被寄生粘虫海藻糖含量为46.82 μg/mL, 未被寄生粘虫含量为26.72 μg/mL。在滞育与非滞育两种条件下, 寄生与未被寄生寄主脂类和蛋白含量没有显著性差异。结果说明: 寄生蜂的存在使寄主血淋巴中的糖原含量增高; 非滞育条件是影响被寄生粘虫海藻糖含量变化主要因素; 粘虫对中红侧沟茧蜂的寄生表现相当强的适应性和忍受力。     

Fate of glucose in haemolymph of the American cockroach, Periplaneta americana

The rate of removal of high concentrations of glucose (10 μg/μl haemolymph) from haemolymph of adult male cockroaches, Periplaneta americana, was studied in normal and ligated insects. More than 50% of the injected glucose is removed from the haemolymph of normal insects within 20 min of injection. A period of rapid trehalose synthesis occurs during the initial 10 min following injection of glucose into the haemocoele, and this is succeeded by a period of glycogen synthesis. The results are discussed in terms of earlier observations on ‘stress-induced hypertrehalosemia’ and the possible involvement of a glycogenic agent.     

Effect of Ovaprim doses and latency periods on induced spawning of Clarias batrachus: observation on larval deformity

Induced spawning of C. batrachus was conducted at different Ovaprim dose and latency period combinations to observe the deformed larvae among the hatchlings. For the purpose, four doses of Ovaprim (0.5, 1.0, 1.5 and 2.0 ml/kg body weight) and five latency periods (11, 14, 17, 20 and 23 hr) were considered in 20 different combinations. There were no deformed larvae in the females injected with all four doses and stripped at 11 hr latency, as the eggs did not hatch. The percentage of deformed larvae (4-7%) did not vary significantly at 1.0-2.0 ml dose level in combination with 14-17 hr latency periods. While increasing the latency period beyond 17 hr at 1-1.5 ml dose level, the percentage of deformed larvae increased significantly and touched as high as 11%. The results indicated that 1-1.5 ml dose in combination with 14-17 hr latency are suitable to reduce the deformed larvae among the hatchlings during induced spawning of C. batrachus.     

Carbohydrate and fatty acid titres during flight of the migrant noctuid moth,Anticarsia gemmatalis Hübner

Haemolymph concentrations of total carbohydrate and fatty acids were determined in velvetbean caterpillar (Anticarsia gemmatalis Hübner, Lepidoptera: Noctuidae) adult females throughout a 4-hr period of tethered flight. Total carbohydrate concentration decreased from approx. 30 to 10 μg/μl during the first 45 min of flight. Total fatty acid concentration increased from approx. 20 to 40 μg/μl during the first 60 min of flight and then declined to and stabilized at preflight levels. The decrease in wet weight (from approx. 97 to 80 mg/moth) during flight was probably due to defecation since no change in dry weight or haemolymph volume occurred. After 4 hr of flight, no apparent change in whole body lipid content (approx. 12 mg/moth) was observed but the much smaller carbohydrate content was reduced approx. 80% (from approx. 0.6 to 0.1 mg/moth). Approximately equal amounts (approx. 360–550 μg) of carbohydrate and lipid were removed from the haemolymph during 4 hr of flight. Changes in the haemolymph concentrations of palmitic, oleic and linoleic acids correspond to the changes in total fatty acid concentration of the haemolymph, indicating that these are the major components of the lipid mobilized and utilized during flight of A. gemmatalis.     

Effects of methoprene,a juvenile hormone analogue,on the larval and pupal stages of the yellow fever mosquito, Aedes aegypti

Exposure of early fourth-instar larvae of Aedes aegypti to the juvenile hormone analogue Altosid ZR15^® (methoprene) significantly increased the concentration of carbohydrates in the haemolymph of late fourth-instar larvae and reduced the haemolymph carbohydrate concentration of 24-h-old pupae relative to controls. Such treatment also effected a decline in haemolymph amino nitrogen levels of the pupal stage and a depletion of haemolymph proteins in late fourth-instar larvae as well as pupae. Two of nine protein fractions in the haemolymph of larvae were significantly depleted following methoprene treatment. Fourteen soluble protein fractions were present in the haemolymph of control pupae; two of these were missing from the pupae which were treated as larvae with methoprene. A further protein fraction, common to the haemolymph of both treated and control pupae, was significantly reduced in concentration as a consequence of exposure to methoprene. The juvenile hormone analogue impaired the capacity of the fat bodies of late fourth-instar larvae and pupae to synthesise proteins, resulting in a lowered concentration of fat body proteins. Glycogen levels in the fat bodies of treated larvae were significantly lower than in controls and glycogenolysis was suppressed due to an overall depletion of glycogen phosphorylase and, in pupae, a lowered ratio of active: inactive enzyme. The data are consistent with the proposition that the juvenile hormone analogue elicits neuroendocrinological changes in the target insect.     

Parasitism enhances the induction of glucogenesis by the insect, Manduca sexta L

Metabolic alterations that accompany parasitism of invertebrate animals can play an important role in parasite development. Employing 13C NMR, this study examined pyruvate cycling from (2-(13)C)pyruvate in the lepidopteran insect Manduca sexta, and the effects of parasitism by the hymenopteran Cotesia congregata on the gluconeogenic formation of trehalose, the haemolymph or blood sugar of insects. Larvae were maintained on a semi-synthetic sucrose-free diet, or on the same diet with sucrose at 8.5 g/l. Pyruvate cycling was evident from the 13C enrichment in C3 of alanine, derived following carboxylation to oxaloacetate, and was similar in parasitized and normal insects regardless of diet. Trehalose was formed following de novo synthesis of glucose, and net synthesis was estimated from the 13C distribution in trehalose and alanine. The 13C-enrichment ratio [2trehalose C6/alanine C3] is an indicator of the level of gluconeogenesis relative to glycolysis, both enrichments were derived from (2-(13)C)pyruvate in the same manner. The ratio was greater than unity in all insects, regardless of diet, but was significantly greater in parasitized larvae, demonstrating an enhanced level of gluconeogenesis. This was confirmed by analysis of the 13C distribution in trehalose and glutamine derived from (3-(13)C)alanine. Despite enhanced de novo trehalose formation in parasitized insects, the haemolymph sugar level was similar to that of normal larvae. Because haemolymph trehalose regulates dietary carbohydrate intake, but not gluconeogenesis, the results suggest that accelerated induction of gluconeogenesis is an adaptive response to parasitism that provides increased carbohydrate for parasite growth and simultaneously maintains nutrient intake.     

Haemolymphal activation of protyrosinase and the site of synthesis of haemolymph protyrosinase in larvae of the fleshfly, Sarcophaga barbata

When whole blood from 5 day third instar larvae of the fleshfly, Sarcophaga barbata was incubated under nitrogen at 25°C for 16 hr in the presence of salivary glands there was an increase in its protyrosinase content, which amounted to 53% of that which occurs in vivo over the same period. The protyrosinase in ammonium sulphate fractions of haemolymph that were allowed to stand at 4°C for 24 hr following the incubation at 25°C was found to have autoactivated. Analysis of all these fractions revealed the presence of a protyrosinase activator in the 30% saturated ammonium sulphate fraction. When proenzyme and haemolymph activator were mixed there followed a lag period before the rapid phase of activation, the duration of the lag being dependent upon the concentration of both proenzyme and activator. The final activity attained was dependent upon the concentration of proenzyme, but was independent of the activator concentration and was comparable to that obtained using the cuticle activator. The level of activator in the haemolymph increased as larvae aged from 4 to 7 days.The effect of several compounds on the catecholase activity of the activated haemolymph protyrosinase and on the cuticle enzyme is reported and the significance of haemolymphal activation of protyrosinase is discussed.     

Inorganic ion composition of haemolymph of the cecropia silkmoth: changes with diet and ontogeny

The levels' of sodium, potassium, magnesium, calcium, chloride, trehalose, and osmotic pressure in haemolymph were studied during ontogeny in the silkmoth Hyalophora cecropia, reared on either foliage or an artificial diet. Potassium and calcium in haemolymph changed little with ontogeny or diet, and averaged 35 and 10 m-equiv/l., respectively. The haemolymph levels of sodium and chloride were greater in larvae fed on artificial diet than in those on foliage, reflecting the levels in the respective diets; after cessation of feeding, the levels in haemolymph of the two groups approached common values (sodium 1–2 m-equiv/l.; chloride 20 m-equiv/l.). Magnesium was higher in haemolymph of foliage-fed larvae (100 m-equiv/l.) than in diet-fed larvae (65 m-equiv/l.), and in both groups declined after spinning to an average level of 40 m-equiv/l.Haemolymph from fifth instar Manduca sexta larvae reared on an artificial diet had ion levels very close to those in Cecropia similarly reared. Haemolymph of Danaus plexippus at three stages of development was also similar, but showed some quantitative differences from the other species.     

几种植物源化合物对棉铃虫海藻糖酶活性及相关碳水化合物含量的影响

碳水化合物对昆虫的能量代谢和物质合成具有重要的作用。本研究选用2种一般性生物碱（氢溴酸东莨菪碱和烟碱）以及2种β-葡萄糖苷类化合物（七叶灵和皂角苷）, 研究其在不同浓度下对棉铃虫Helicoverpa armigera (Hübner)幼虫体内海藻糖酶活性及相关碳水化合物代谢的影响。结果表明: 用饲喂法处理3龄幼虫96 h后, 皂角苷对棉铃虫幼虫的活体抑制效果明显, 且随添加物浓度增高, 棉铃虫死亡率上升, 10, 20, 40 g/L浓度下棉铃虫的均重分别是0.194, 0.089和0.034 g, 分别为对照的86.99%, 39.91%和15.24%。对海藻糖酶活性及其相关代谢酶的测定结果表明, 2种苷类化合物显著抑制中肠海藻糖酶活性, 饲喂40 g/L皂角苷的试虫中肠海藻糖酶比活力仅是对照组的54.21%; 饲喂30 g/L七叶灵的试虫中肠海藻糖酶比活力为对照组的83.73%。而2种生物碱类化合物显著抑制血淋巴和脂肪体中海藻糖酶活性, 20 g/L氢溴酸东莨菪碱对棉铃虫血淋巴和脂肪体组织的海藻糖酶活性抑制率分别为7.24%和71.43%; 而20 g/L烟碱对试虫血淋巴和脂肪体组织的海藻糖酶活性抑制率为26.29%和33.44%。用氢溴酸东莨菪碱、 烟碱和七叶灵处理试虫后, 血淋巴海藻糖含量都有所增高。4种化合物能够导致试虫糖原磷酸化酶活性变化, 其中, 皂角苷在中肠和脂肪体表现为显著抑制作用, 而随外源化合物浓度变化, 糖原含量和糖原磷酸化酶活性表现为此消彼长关系。饲喂4种植物源化合物的试虫血淋巴中葡萄糖浓度变化和其海藻糖变化一致。本研究证明β-葡萄糖苷类化合物是海藻糖酶抑制剂, 在作为先导化合物进行农药创制开发方面具有重要意义。     

Water and carbohydrate levels at different developmental stages and dynamics in hibernating pupae of Pieris melete (Lepidoptera: Pieridae)

For insight into the physiological indicators of diapause in Pieris melete, water and carbohydrate (glycogen and trehalose) levels were measured under both natural and laboratory conditions. The highest water content (3.71–3.79 mg/mg dry weight) was found in larvae and developing pupae, which was substantially higher than in diapausing pupae (2.59 mg/mg dry weight). Water content was almost stable during diapause, except for individuals approaching diapause termination (3.43–3.58 mg/mg dry weight). The total carbohydrate level was significantly higher in pre‐pupae (47.41 μg/mg) compared to larvae (22.80 μg/mg) and developing pupae (21.48 μg/mg). The highest level of trehalose was detected in winter diapausing pupae, and no trehalose was found in larvae or developing pupae. Levels of glycogen were highest in pre‐pupae and lowest in diapausing pupae. Levels of total carbohydrate decreased as diapause proceeded, and no significant changes were found in trehalose levels for diapausing pupae under natural conditions or treated for 60–90 days at 5°C. Pupae treated at 20°C for 60–90 days had significantly lower levels of trehalose than those treated for 30 days. Glycogen content was relatively stable at 5°C, but increased after treatment under natural conditions and 20°C for more than 60 days. These results suggest that the dynamics of water and carbohydrate levels are potential physiological diapause indicators, which show metabolic differences between trehalose and glycogen during diapause development.     

Interrelationships between haemolymph lipid and carbohydrate during starvation in Locusta

During starvation in adult female Locusta, the haemolymph total lipid concentration increases markedly while that of the total carbohydrate decreases. The majority of the increased haemolymph lipid is diglyceride and 75% of this is associated with a high molecular weight lipoprotein (A⁺) which disappears rapidly after feeding when the total lipid concentration is restored to the normal resting value. The effect of feeding can be mimicked by injecting or feeding starved locusts with sugars but not with protein. The lowering of the haemolymph total diglyceride concentration in starved locusts by injection of carbohydrates is dose-related and, at doses in excess of 4 mg per locust, almost normal values (for fed locusts) are obtained within 6 hr. It is suggested that in the haemolymph there is an inverse relationship between the concentration of diglyceride and that of trehalose.     

Population pharmacokinetics of methotrexate in the guinea pig.

The population pharmacokinetics of an antitumoral and antiinflammatory agent, methotrexate (MTX), a folic acid antagonist, was studied in guinea pigs. Animals received an acute intraperitoneal injection of 0.25, 1 or 5 mg/kg MTX. Blood sampling was carried out for 12 hrs. after MTX administration and plasma drug concentrations were measured by fluorescence polarization immunoassay. The pharmacokinetic (PK) parameters were computed using the bayesian population model. MTX reached the level of detection at 3 hrs. for the animals injected with the lowest dose (0.25 mg/kg), at 3.5 hrs. for those animals which had the intermediate dose (1 mg/kg) and more than 6 hrs. for animals having received the highest dose (5 mg/kg). Each kinetic parameter (half life, total clearance - CLt, volume of distribution at steady state - VDSS, mean residence time - MRT - and area under curve - AUC) didn't show any significant difference between doses. MTX kinetic was linear for the first two doses (0.25 and 1 mg/kg MTX) and non-linear thereafter. MTX presented a one compartment distribution.     

Continuous cultivation of bakers' yeast: Change in cell composition at different dilution rates and effect of heat stress on trehalose level

The cell composition of bakers' yeast in a continuous culture was determined for different dilution rates. Also, the cellular response to heat stress in terms of trehalose, RNA, glycogen and protein was determined at a specified dilution rate of 0.1/h. The amount of storage saccharides, trehalose and glycogen, was found to decrease whereas the amount of RNA and protein increased with increasing dilution rates. As the dilution rate was increased from 0.1 to 0.4/h at 0.05 intervals the steady-state trehalose content decreased from 33 to 8.6 mg/g biomass, and glycogen content from 150 to 93 mg/g biomass. On the other hand, the protein content increased from 420 to 530 mg/g biomass and the RNA content from 93 to 113 mg/g biomass. Heat stress was applied by increasing the medium temperature from 30 to 36, 38 or 40°C at constant dilution rates. The highest amount of trehalose accumulation, 108 mg/g biomass, was achieved when heat stress at 38°C was applied. The protein content, on the other hand, decreased from 350 to 325 mg/g biomass at the end of the experiment.     

Effect of phenol and pesticides on the physicochemical properties of the hemolymph in fresh-water gastropod mollusks (Gastropoda, Pulmonata) infected by trematode parthenitae

The effect of solutions of phenol (100, 250, 400 mg/l), copper sulfate, carbophos and bazudine (0.01, 0.1, 1.0 mg/l) on physical and chemical properties of haemolymph of Lymnaea stagnalis (L.) and Planorbarius corneus (L.) infected with parthenitae of trematodes was studied. Haemolymph viscosity decreases and its active reaction shifts to weakly acid one. Haemolymph density decreases only in solutions of carbophos and bazudine. With heavy infection the concentration of haemoglobin in haemolymph of P. corneus does not change under the effect of phenol but the total volume of haemolymph reduces considerably.     

Studies on l-glutamate in insect haemolymph.

ABSTRACT. The neuromuscular junctions of abdominal body wall muscles of larval Lucilia sericata are mainly superficial, with no glial sheath, and are surrounded by a well-developed subsynaptic reticulum. Injection of l -glutamate into the haemolymph of adult male Locusta migratoria and larvae of Lucilia sericata caused reversible effects on motor activity. These effects were quantified and dose—response curves are presented. The effective concentration of the injected doses is low enough to be physiologically relevant. Injection of l -aspartate into Locusta haemolymph affected motor activity. Injection of l -aspartate into Lucilia larvae produced no detectable effect. Injections combining l -aspartate and l -glutamate into Lucilia larvae had a synergistic effect on the duration of paralysis, compared with the same concentration of l -glutamate injected alone.     

In vitro-cultured bovine granulosa and oviductal cells secrete sperm motility-maintaining factor(s)

Since bovine cumulus oophorous and oviductual cell cultures are known to support and maintain frozen-thawed bovine sperm viability and motility for extended time periods, we investigated whether granulosa cell (GC)- and oviductual cell (OC)-conditioned media have similar effects. GC and OC were cultured for 3 days in TCM-199 medium supplemented with 10% fetal calf serum. At that time, the supernatant was discarded from GC and the monolayers were covered with Sp-TALP medium containing 6 mg/ml bovine serum albumin, while the OC were recovered by centrifugation and transferred to culture bottles containing Sp-TALP. Two days later, GC-conditioned and OC-conditioned Sp-TALP were recovered and dialyzed, and their retentates were lyophilized. Bovine follicular fluid (BFF) was also dialyzed, and its retentate was lyophilized. When sperm were incubated in GC- or OC-conditioned media, motility remained above 62% and 42% at 6 hr and 30 hr, respectively, and motility was higher than that of the control both at 6 hr (39%; P < 0.001) and at 30 hr (9%; P < 0.0001). Similarly, when sperm were incubated in the lyophilized retentates of GC- and OC-conditioned media and in BFF at a dose of 0.1, 0.5, or 1.0 mg/ml, the motility rates were higher both at 6 hr (P < 0.05) and at 30 hr (P < 0.01) compared to the control. The increase in motility was dose dependent; a 1.0 mg/ml dose improved (P < 0.05) motility compared to a 0.1 mg mg/ml dose. Heat treatment of the retentates of GC, OC, and BFF at 55°C for 30 min did not destroy their ability to support and maintain motility. However, heating at 100°C for 5 min destroyed their ability to support motility. Molecular sieving of retentates on Sephancryl S-300 yielded fractions that were highly effective (P < 0.01) in enhancing and maintaining motility compared to the other fractions. In conclusion, GC and OC secrete nondialyzable, heat-labile factor(s), which support and maintain sperm viability and motility for up to 30 hr. © 1994 Wiley-Liss, Inc.