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1.
W L Daniel 《Experientia》1987,43(11-12):1209-1211
Arylsulfatase B activity levels were approximately 2-3-fold higher in adult C57BL/6J liver and kidney compared to corresponding tissues from A/J inbred mice. In vivo incorporation of tritiated leucine into C57BL/6J hepatic arylsulfatase B reached a maximum approximately 15 h after injection. The label was cleared from C57BL/6J arylsulfatase B with an apparent half-life of 36 h. The relative rates of synthesis of C57BL/6J and A/J arylsulfatase B were similar; however, the A/J enzyme was cleared more rapidly from liver tissue. C57BL/6J kidney arylsulfatase B appeared to be synthesized at a 2-3-fold higher rate than the corresponding A/J enzyme. These trends suggest genetic regulation of arylsulfatase B is effected through different means in liver and kidney from adult mice of these two inbred strains.  相似文献   

2.
Twice daily s.c. injection of 5 ng or 50 ng of SMS 201-995 between 25 and 55 days of age induced a significant retardation of normal mammary gland growth in C3H/He virgin mice, associated with the reduced plasma GH level. Meanwhile, plasma prolactin level and the pattern of estrous cycle were affected little by SMS treatments. The results indicate an involvement of GH in normal mammary gland growth in mice.  相似文献   

3.
Summary Twice daily s.c. injection of 5 ng or 50 ng of SMS 201-995 between 25 and 55 days of age induced a significant retardation of normal mammary gland growth in C3H/He virgin mice, associated with the reduced plasma GH level. Meanwhile, plasma prolactin level and the pattern of estrous cycle were affected little by SMS treatments. The results indicate an involvement of GH in normal mammary gland growth in mice.  相似文献   

4.
Summary Autoradiographic studies using3H-uridine in the salivary gland of adultLygaeus sp. were carried out. The gland cell nuclei, particularly the multiple nucleoli, are the sites of incorporation of the label exhibiting RNA synthesis. The labelled molecules (RNA) are transported to the cell cytoplasm and then into the gland lumen in which no turnover of the radioactivity is observed.I am grateful to my teacher, Prof. P. S. Ramamurty, School of Life Sciences, University of Hyderabad, for his constant inspiration. Grateful acknowledgement is made to Prof. J. P. Thapliyal, Dept of Zoology, B. H. U. for encouragement and to Dr Om Prakash, Dept of Biochemistry, B. H. U. for his valuable criticism.  相似文献   

5.
Summary It is shown that both follicle cell sheath and ooplasm contain only small quantities ofHelix-hydrolyzable ecdysteroid conjugates and that 20-hydroxy-ecdysone is the predominant free ecdysteroid. Its concentration is very high in the follicle cell sheath immediately before chorion formation (6825 ng/g) and much lower after chorion formation (150 ng/g), while it is 234 ng/g and 95 ng/g in the ooplasm at the same stages respectively.Thanks are due to Dr J.D. O'Connor (Los Angeles) for the ecdysone antiserum, to Dr J. Koolman (Marburg) for 23,24-[3H]-ecdysone and to Mrs A. Tschan for technical assistance. A fellowship to X. Zhu from the Chinese Ministry of Education and financial support from the Swiss National Science Foundation (grant no. 3.714-0.80 to B. Lanzrein) are gratefully acknowledged.  相似文献   

6.
S L Bond  S M Singh 《Experientia》1988,44(9):782-785
We studied mice from five strains (BALB/c, C3H/HeSnJ, C57BL/6J, Csb and 129/ReJ) at two ages (young, 10 +/- 1 weeks; and old, 67 +/- 3 weeks) for the induction of sister chromatid exchanges (SCEs) in vivo by methyl nitrosourea (MNU). The SCE frequency is genotype-specific. The F1 phenotype resembles the 'low' responding parent. SCE induction is significantly lower in the older animals of each strain than their younger counterparts, and the reduction of SCE/cell with old age is strain-specific. A general explanation for these results must include strain differences in relative mutagenic sensitivity, genotype-specific pattern of reduction in DNA repair and other such factors affecting SCE formation, with old age.  相似文献   

7.
Summary The chlorophyll a and protein contents of invertebrates containing autotrophic symbionts are indices of symbiont and host biomass, respectively, and the chlorophyll a content per unit protein is a good measure of symbiont: host ratio. For three different associations, the chlorophyll a content per unit protein is 0.01–0.02 g g–1.The hydra andE. viridis were provided by M. H. Christopher and J. R. Turner. I thank Professor D. C. Smith, Dr J. B. Searle and Dr T. A. V. Rees for the valuable comments on drafts of this paper. This work was supported by research grants from S.E.R.C.  相似文献   

8.
Summary The attraction ofS. scolytus to the components of Multilure is described. 4-Methyl-3-heptanol is an attractant which is synergised bya-cubebene. Multistriatin appears to be an inhibitor. A combination of 4-methyl-3-heptanol and cubeb oil is more effective as a bait forS. scolytus than Multilure.We thank Mr A. K. Hughes and Mr J. Boswell for their cooperation in allowing us to conduct experiments on Parham Estate; Mr D. Mobbs and Mr C. Thorne for the statistical analyses; Dr J. W. Peacock for samples of mixed isomers of multistriatin and distilled cubeb oil; Mrs J. Allsop and Mr N. J. Fielding for technical assistance. We are grateful to Mr D. Bevan, Dr J. H. Borden, Dr J. F. Grove and Prof. A. W. Johnson for their interest and encouragement.  相似文献   

9.
Summary A strain ofStreptomyces contains a mixture (ca. 3:1) of 2d-hydroxy-12l-methyltetradecanoic and 2d-hydroxy-13-methyltetradecanoic acids; it has the same properties as a similar mixture prepared by synthesis.

11e Communication sur la chimie des micro-organismes; 10e communication:C. Lacave, J. Asselineau etR. Toubiana, Europ. J. Biochem.2, 37 (1967).  相似文献   

10.
The sex-dependent effect of lauroyl-L-Ala-D--Glu-L,L-A2pmNH2 (LtriP, RP 56142) on hepatic microsomal cytochromes P 450 (cyt P 450) was studied in three mouse strains NMRI, C3H/OuJ and C3H/HeJ. In NMRI and C3H/OuJ, strains which are responsive to bacterial lipopolysaccharides (LPS-responsive), regardless of the sex of the mouse, significant decrease in the amount of cyt P 450 was observed after LtriP treatment, with a concomitant reduction in ethoxyresorufin-O-deethylase (cyt P 450 1A-dependent) and 7-ethoxycoumarin-O-deethylase activities. This was not seen in C3H/HeJ (LPS-hyporesponsive) mice. These effects may be related to LtriP-dependent cytokine induction, since neither LtriP nor LPS stimulated interleukin-1 (IL-1) secretion by C3H/HeJ macrophages. 11- and 12-hydroxylations (11- and 12-OH) of lauric acid were compared in C3H/OuJ and C3H/HeJ mice. LtriP depressed the total enzymatic conversion of lauric acid in the two strains without modification of the 11/12-OH ratio for C3H/OuJ or male C3H/HeJ mice. However, in females C3H/HeJ mice this decrease was particularly significant and concerned especially the 12-OH activity (a marker of cyt P450 4A family). Although males of the three strains were more sensitive to irradiation than females, LtriP exerted a sex-independent radioprotection on NMRI and C3H/OuJ mice. Its radioprotective effect was illustrated by the preservation of all the enzymatic activities studied in treated NMRI mice, contrary to irradiated control animals. In contrast, for the C3H/HeJ strain, males were not protected by LtriP treatment and, furthermore, females showed a marked sensitization to irradiation.The effects in CH3/HeJ strain implicate LtriP in the control of cyt P 450 induction and of sensitivity to irradiation independently of IL-1 induction.  相似文献   

11.
Summary We studied mice from five strains (BALB/c, C3H/HeSnJ, C57BL/6J, Csb and 129/ReJ) at two ages (young, 10±1 weeks; and old, 67±3 weeks) for the induction of sister chromatid exchanges (SCEs) in vivo by methyl nitrosourea (MNU). The SCE frequency is genotype-specific. The F1 phenotype resembles the low responding parent. SCE induction is significantly lower in the older animals of each strain than their younger counterparts, and the reduction of SCE/cell with old age is strain-specific. A general explanation for these results must include strain differences in relative mutagenic sensitivity, genotype-specific pattern of reduction in DNA repair and other such factors affecting SCE formation, with old age.  相似文献   

12.
3H Trp and 14C Lys incorporation in proteins from chromatin of normal and regenerating animals, purified on metrizamide, show that the synthesis of these proteins is different in the two cases.  相似文献   

13.
Summary In the present paper, an extension is presented of an earlier described method, by which the methylating capacity of the pineal gland can be determined. Supplementary to the earlier method, the synthesis of melatonin and 5-methoxytryptophol can now be qualified and quantified separately.The authors wish to express their gratitude to Prof. Dr J.C. van de Kamer and Dr F.C.G. van de Veerdonk for their stimulating interest in these studies.  相似文献   

14.
Summary Sulpiride administration to rats releases prolactin and increases DNA replication in the anterior pituitary gland. Clomiphene prevents the stimulation of DNA synthesis produced by sulpiride, but does not affect prolactin release from the gland. These findings suggest that the intracellular prolactin content of the anterior pituitary gland plays a role in the regulation of DNA synthesis through a mechanism mediated by oestrogens.This work was supported by PLAMIRH 99.178.1.78, by the Consejo Nacional de Investigaciones Científicas y Técnicas and by the Comisión Nacional de Energía Atómica (Argentina). We are grateful to Dr P. Scacchi for performing the radioimmunoassay and to Prof. C. J. Gómez for the opportunity to perform this work.  相似文献   

15.
After perfusion by oleic acid (9-10(-3)H) and glycerol (1(-14)C) previously starved Wistar rats, the synthesis of hepatic TG and PL follows the two following different method: -- during the first minutes of perfusions, the most important method synthesis of TG and especially of PL is a de novo synthesis utilizing glycerol and the exogenous AG. The TG synthesized are 18:1 18:1 18:1 and 16:0 18:1 18:2 the PL synthesized are LP, AP and LPC; -- during perfusions of long duration (30, 60, 120 min.), the major method of synthesis of TG and PL is an active exchange of AG of the endogenous glycerolipids. The TG synthesized are 16:0 18:1 18:1 and 16:0 18:1 18:2 the PL synthesized are PE and PC.  相似文献   

16.
Summary The concentrations of -phenylethylamine,p-tyramine,m-tyramine,m-octopamine and tryptamine in the ganglia or foot muscle ofHelix aspersa range from <0.6 to 11 ng/g.p-Octopamine levels are higher in ganglia (327 ng/g) than in foot muscle (4.1 ng/g). Dopamine and 5-hydroxytryptamine range from 840 to 2710 ng/g while their acid metabolites, 3,4-dihydroxyphenylacetic acid, 3-methoxy-4-hydroxyphenylacetic acid and 5-hydroxyindoleacetic acid range from <20 to 130 ng/g.Acknowledgments. We thank Dr A.A. Boulton for helpful discus sion, Dr D.A. Durden for supervising the mass spectrometric analyses, Dr B.A. Davis for the synthesis of the deuterated standards, G.H. Wheatley, E.P. Zarycki and M. Mizuno for expert technical assistance, and Saskatchewan Health and the MRC of Canada for providing financial support.  相似文献   

17.
Summary (3H)Nitrendipine binding to the bovine tracheal muscle membrane at 25°C was rapid, saturable (Bmax=14.8±3.9fmol/mg protein) and of high affinity (Kd=0.15±0.04 nM). The rank order of Ca2+ antagonists competing for airway (3H)nitrendipine binding was nitrendipine nisoldipine nifedipine » verapamil. Cromolyn, however, neither inhibited nor increased the binding.J.B.C. is a visiting associate professor at the NYMMC. We thank Ms. Pang-jang Chang for technical assistance. This work is supported by a grant (NSC 72-0412-BO10-R20) from the National Science Council, ROC. To whom reprint requests should be addressed: Allergic Disease Center, Creighton University School of Medicine, Omaha, Nebraska 68178.  相似文献   

18.
B Stark  U Keller 《Experientia》1987,43(10):1104-1106
The effect of norepinephrine on fatty acid synthesis (3H2O incorporation into fatty acids), on fatty acid oxidation to CO2 and on ketogenesis was studied in isolated hepatocytes of fed rats. After incubation with norepinephrine (50 microM), lipogenesis was lower (5.7 +/- 1.1 nmoles 3H2O incorporated into fatty acids/mg dry weight/30 min) than in controls (7.5 +/- 1.7; n = 6, p less than 0.02). In contrast, (1-14C) palmitate conversion into total ketone bodies was increased to 10.9 +/- 1.8 nmoles/mg/30 min with norepinephrine, vs 8.5 +/- 1.6 in controls (p less than 0.05), and more (1-14C) palmitate was converted to 14CO2 with norepinephrine than in controls (1.48 +/- 0.10 nmoles/mg/30 min vs 1.06 +/- 0.11, p less than 0.05). The inhibitory effect of norepinephrine on lipogenesis was abolished by addition of the alpha 1-receptor blocker prazosin, but not by alpha 2 or beta-blockers. The results demonstrate that the ketogenic effect of norepinephrine is coupled with an inhibitory effect on lipogenesis which may be explained by diminished activity of acetyl-CoA carboxylase, diminished formation of malonyl-CoA and decreased activity of carnitine palmitoyl transferase I.  相似文献   

19.
20.
Summary The synthesis and antischistosome properties of 5-(hydroxyimino)-4-methoxy-2-(pivaloylimino)thiazolidine-3-acetamide (1) are described. The compound was prepared by reduction of the nitrothiazoline (2) with stannous chloride in methanol, and represents the first example of a reduced nitroheterocyclic compound showing potent schistosomicidal properties. The possible relationship of compounds such as1 to the as yet unidentified reduced active but toxic entities formed in vivo from nitroheterocyclics like metronidazole is discussed.Acknowledgments. The authors are grateful to Dr A. J. Everett and his staff for the physical chemistry measurements, and to Mr G. Dickerson for the antischistosome testing.  相似文献   

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