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1.
A highly purified gonadotropic hormone preparation has been obtained from chum salmon (Oncorhynchus keta) pituitaries by extraction with ethanolic or aqueous buffer, affinity chromatography on Con A Sepharose and gel filtration on Sephadex G-75 superfine. A purified fraction from Sephadex G-75 averaged 448 mug NIH-LH-S18/mg glycoprotein as measured by the uptake of radiophosphate into chick testes. A total of 1.1 g of salmon gonadotropin (s) (SG)/kg fresh tissue was recovered when the isolation began with an aqueous extraction. Analytical polyacrylamide gel electrophoresis (P.A.G.E.) of the purified fraction from Sephadex G-75 displayed a single broad zone in non-dissociating conditions and two bands in 8 M urea. Polyacrylamide gel electrofocusing yielded six sharp bands with an isoelectric point range of 4.38 to 5.05, and four bands with an isoelectric point range of 4.31 to 4.95 in 8 M urea. A molecular weight of 41,000 was determined by gel filtration. A subunit molecular weight of 17,800 +/- 10% was found by P.A.G.E. in 0.1% sodium dodecyl sulphate (SDS), suggesting that native SG consists of two subunits. Purified preparations were highly stable in Tris-Cl buffers and retained their activity for several months when stored at -73 degrees C.  相似文献   

2.
We reported the presence of a 80 kDa polypeptide in porcine follicular fluid that inhibited the binding of 125I-radiolabelled hFSH as well as hCG to the rat ovarian gonadotropin receptors. In the present study, the biological activity of the receptor binding inhibitor is determined using an in vitro bioassay procedure. Granulosa cells isolated from PMSG primed immature rat ovaries respond to exogenously added gonadotropins in terms of progesterone production. Addition of fractions containing the gonadotropin receptor binding inhibitory activity inhibited progesterone production stimulated by the gonadotropins in a dose-dependent fashion. The receptor binding inhibitory activity was also capable of inhibiting progesterone production stimulated by PMSG, which has both FSH- and LH-like activities in rats. In contrast, progesterone production stimulated by dbcAMP was not inhibited by the receptor binding inhibitor. This result indicates that the site of action of the inhibitor is proximal to the formation of the cAMP. The above observations point out to a possible role for this factor in modulating gonadotropin activity at the ovarian level.  相似文献   

3.
1. A single, high specific activity carbonic anhydrase (CA) isozyme was present in erythrocytes of the teleostean species Salmo gairdneri (rainbow trout). 2. Purification of trout CA to homogeneity was accomplished using chloroform ethanol extraction, Sephadex G-75 gel filtration, and DEAE Bio-Gel anion exchange chromatography. 3. Trout CA was a zinc metalloenzyme of mol. wt 28,300 and pI9.3. 4. Amino acid analysis indicated the presence of 6 half-cystine residues per enzyme molecule, and the presence of a sulfhydryl reducing agent was required to maintain full activity in vitro. 5. Sulfhydryl modification with both N-ethylmaleimide and acrylonitrile indicated the presence of 3 reactive sulfhydryl groups per CA molecule. Modification of those groups had no direct effect on enzyme activity, but modified CA was no longer subject to inactivation by oxidizing conditions.  相似文献   

4.
Follicular fluid obtained from medium or large bovine ovarian follicles inhibited ovarian luteinizing hormone/human chorionic gonadotropin sensitive adenylate cyclase in a dose-dependent manner (I50 = 3 mg follicular fluid protein/ml). The inhibitory activity was excluded by Sephadex G-10 and was fully retained following treatment with charcoal. Fluoride-stimulated enzyme activity was not inhibited. Binding of 125I human chorionic gonadotropin to ovarian plasma membranes was only slightly reduced by the follicular fluid. The post-microsomal supernatant of homogenates from ovaries of immature (27-day-old) rats collected 24–36 h after treatment with 15 i.u. of pregnant mare serum gonadotropin also inhibited luteinizing hormone-sensitive adenylate cyclase. The extent of this inhibition seemed to decline with follicular maturation. The possibility is raised that ovarian sulfated glycosaminoglycans are responsible for the observed inhibition of adenylate cyclase.  相似文献   

5.
The metallothionein (MT) gene expression profile was followed in rainbow trout during early embryo development and in liver and gonads during the period of sexual maturation. The hepatic MT mRNA levels increase at the end of sexual maturation in both male and female rainbow trout. Although both isoforms of MT mRNA accumulate in the liver, there is a preferential increase in MT-A in the female liver. Concomitantly with this increase in MT there is a redistribution of zinc and copper to MT. In the juvenile female there is an abundance of MT mRNA in the ovaries. This is correlated to high levels of zinc in the MT fraction upon Sephadex G-75 chromatography. During ovary development the MT mRNA levels and the MT-bound zinc levels drop, with an increase in zinc being bound to high-molecular-mass proteins. At ovulation most of the zinc is found in the membrane portion upon centrifugation. In contrast to the ovaries, there are no apparent changes in either trace metal distribution or MT mRNA levels during testis development. In the developing embryo there is an increase in MT-bound copper at gastrulation. This is accompanied by an increase in both isoforms of MT mRNA. At hatch both the copper and zinc levels increase in the MT fraction, with a concomitant increase in mainly MT-A mRNA. These findings indicate that the variations in MT mRNA levels during development are closely associated with metal regulation.  相似文献   

6.
Purification to apparent homogeneity of inactive kallikrein from rat urine   总被引:1,自引:0,他引:1  
Inactive kallikrein was purified from rat urine by a procedure including ammonium sulfate fractionation, DEAE cellulose chromatography, phenyl-Sepharose CL-4B chromatography, and gel filtration on Sephadex G-100 and Sephadex G-75 columns. The resulting preparation was essentially homogeneous, as assessed by polyacrylamide gel electrophoresis. This preparation migrated as a single protein band on a SDS-polyacrylamide gel and the molecular weight was 41000. The purified material underwent marked activation by trypsin, but not by deoxycholate, Triton X-100, SDS or acidification. These results indicate that the purified inactive kallikrein is the precursor rather than a complex with a substance binding to the active form of kallikrein.  相似文献   

7.
Oidiodendron kalrai yeast-phase cells demonstrate proteolytic activity. Some of the proteolytic enzymes of the crude extract were purified by a combination of ammonium sulfate precipitation, Sephadex G-200, and diethylaminoethyl (DEAE) cellulose column chromatography. At least six proteins exhibiting a range of proteolytic activities could be identified by these procedures. Purity of the enzyme fractions obtained from the DEAE-cellulose columns was tested by running polyacrylamide gels.  相似文献   

8.
Transplantation of testes between isogenic rainbow trout males has been recently demonstrated. The objective of the present investigation was to determine if ovaries detached from the body wall and removed from the abdominal cavity would reestablish themselves when autografted to an ectopic site. In the first experiment, eleven sexually immature, female rainbow trout were laparotomized midventrally, and the right ovary was removed and transplanted to the abdominal cavity and positioned along the pyloric cecae on the right side. In the second experiment, the ovary was autografted in four animals as in experiment 1 or was transferred to and allografted in four other sexually immature female trout. The animals were examined three months following surgery. At the termination of experiment 1, the autografted ovaries were present in 73% of the animals; the transplanted ovaries were smaller in size than the intact control ovaries. Histological examination did not reveal any necrotic tissue in these transplanted gonads, and oocyte development was not different between the transplanted and the intact ovary within animal. Transplanted ovaries allografted from another female were not found. Taken together, these data support the conclusion that rainbow trout ovaries detached from the body wall can reestablish their blood supply and maintain ovarian development and that female trout appear to reject gonadal tissue from other individuals of their species.  相似文献   

9.
Labile polyphosphate phosphohydrolase from Endomyces magnusii is 27-fold purified by means of fractionation with ammonium sulphate, gel filtration on Sephadex G-75 and Biogel P-60 and chromatography on DEAE cellulose. Chromatography on DEAE Sephadex A-50, isoelelctric focusing and polyacrylamide gel electrophoresis of the enzyme preparation revealed 3 different fractions with polyphosphate phosphohydrolase activity (PPPH1, PPPH2 and PPPH3). Relative content of these fractions in E. magnusii cells is 30%, 55% and 15% respectively. Isoelectric points are: PPPH1--pH 5.1--5.2; PPPH2--pH 6.0--6.1; PPPH3--pH 6.3--6.4. PPPH1 and PPPH2 are found to be the most labile. PPPH3 is more stable under isolation procedure and storage. The fractions have similar molecular weight (48 000 +/- 3000).  相似文献   

10.
1. The effect of salmon gonadotropin(s) (SG) on cyclic AMP (cAMP) levels in immature trout gonadal tissue of both sexes was measured by radioimmunoassay. 2. A dose-response line was obtained to SG in gonads of both male and female trout. 3. As little as 0.45 SG units (1 SG unit = 1 mug NIH-LH-S18 in the chick bioassay) significantly increased cAMP formation in the presence of 8 mM theophylline; mammalian LH, FSH, LTH, ACTH, TSH and HCG were inactive. 4. The assay for SG was investigated with respect to time of incubation and two phosphodiesterase inhibitors; some conditions for the cAMP radioimmunoassay (cAMP-RIA) were compared.  相似文献   

11.
The insulin-sensitive cAMP phosphodiesterase (PDE) in the microsomal fraction (Fraction P-2) from basal (-insulin) rat adipocytes was stimulated upon incubation with 2 mM ATP plus the soluble fraction from insulin-treated adipocytes (Fraction S-2+). Fraction S-2+ was prepared in the presence of p-nitrophenylphosphate, sodium vanadate, and EGTA. The ATP-dependent stimulation of PDE was routinely 60-70%. The unknown factor in Fraction S-2 was water-soluble, heat-labile, excluded by Sephadex G-50, mostly retained by Sephadex G-100, and not inhibited with 1 microgram/ml heparin, 3 mM CaCl2, or 30 mM NaF. The soluble factor may be a mediator of insulin action on PDE, possibly a protein kinase.  相似文献   

12.
Crude human chorionic gonadotropin (hCG) was found to be several fold more immunosuppressive than purified hCG in human peripheral blood lymphocyte cultures stimulated by phytohemagglutinin, pokeweed, purified protein derivative and allogeneic cells in vitro. Immunosuppression by crude hCG was consistently noted at levels less than 1000 IU/ml and usually 80% inhibition was achieved with doses of 5000–10,000 IU/ml, whereas 40–50% inhibition or less was observed by purified hCG at 10,000 IU/ml. In two crude hCG preparations subjected to Sephadex G-100 chromatography, the fractions that inhibited lymphocyte cultures appeared in the eluate after the major peak of hCG activity. These data indicate that inhibitory substance(s) other than hCG are responsible for most of the immunosuppressive properties of first trimester pregnancy urine. Both crude and purified hCG were stimulatory to human lymphocytes when used alone without mitogens when cultured in fetal calf serum.  相似文献   

13.
In the family Bufonidae, male toads possess rudimentary ovaries, called Bidder's organs, which are attached to the testes. The mechanisms involved in the inhibition of oogenesis in these structures were investigated in male Bufo woodhousii. Orchidectomized and sham-operated animals were injected with gonadotropins (pregnant mare serum gonadotropin [PMSG] + human chorionic gonadotropin [hCG]) for 26 days and the effects of these hormones on oogenesis and steroidogenic activity (3 beta-hydroxysteroid dehydrogenase [3 beta-HSD] and 17 beta-HSD) in the Bidder's organ were quantified. Bilateral orchidectomy alone resulted in the growth of bidderian oocytes and a shift towards later stages of oogenesis. Gonadotropins enhanced this effect and stimulated the proliferation of new germ cells. In the presence of testes, however, bidderian oogenesis remained inhibited despite high levels of circulating gonadotropins. In both ooplasm and follicular layers of the bidderian oocytes of all toads, 3 beta-HSD and 17 beta-HSD activities were detected by histochemistry. Follicular enzymatic activity increased in orchidectomized toads treated with PMSG + hCG but decreased in sham-operated toads treated with gonadotropins. Testis weights, rudimentary oviduct weights, and plasma steroid levels increased in intact toads injected with hCG + PMSG. Gonadotropins had no effect on plasma steroid levels in orchidectomized toads, however. These results suggest that the testes play a major role in the inhibition of oogenesis in Bidder's organs of B. woodhousii and are a major source of androgens. High circulating levels of gonadotropins do not overcome the inhibitory effects of the testes.  相似文献   

14.
Unstimulated P388D1 cells, as well as P388D1 cells stimulated with PHA-activated guinea pig T lymphocytes or LPS, produced a lymphocyte activating factor (LAF). In order to have a chemical basis for comparing this LAF with the LAF produced by normal macrophages, we have analyzed several biochemical characteristics of the P388D1-derived LAF. Sephadex G-75 chromatography of concentrated LAF-containing supernatants from cultures of unstimulated and T cell stimulated P388D1 cells demonstrated that the cell line LAF had a m.w. of approximately 16,000. On DEAE cellulose, the T cell-induced LAF fractionated into at least three major peaks and one minor peak. By using hydroxylapatite chromatography, two of the major peaks of LAF activity were separated from residual contaminating Lowry positive material. LPS-stimulated P388D1 also produced LAF with a m.w. of 16,000. However, the LPS-induced LAF appeared to lack one of the DEAE peaks of LAF activity observed with the T cell-derived LAF. In contrast to LPS, T cells may induce the synthesis and/or release of an additional LAF component or enzymatically modify one or more of the LAF species that are produced in response to both stimulants. Based on the results of chemical characterization studies, the P388D1-derived LAF appears to be similar in size and charge to the lymphocyte activating factor produced by normal macrophages.  相似文献   

15.
Calcitonin was extracted from the pericardium and esophagus of eel in quantities sufficient to permit purification and chemical characterization. Homogeneous calcitonin could be isolated by a six-step fractionation starting from acetone powder of the organs. The fractionation procedure consisted of acid extraction, gel filtration on Sephadex G-75, chromatography on SP-Sephadex C-25, gel filtration on the Sephadex G-50, chromatography on carboxymethylcellulose, and gel filtration on Sephadex G-50. Fractionation of the hormone was monitored by assay of its biological activity and from its behaviour on thin layer chromatography and polyacrylamide gel disc electrophoresis. The hormone contained 32 amino acid residues, like calcitonins from other species of animals, but its amino acid composition was different from those of previously characterized hormones. Eel calcitonin possessed almost the same, or higher, biological activity as the salmon or chicken hormone, which show the highest specific activity among calcitonins so far isolated.  相似文献   

16.
Hypertonic salt extracts prepared from the heart tissues of adolescent CD-1 mice were fractionated on Sephadex G-100 columns. Two separate fractions were obtained. Fraction I, containing the antigenic immunoreactive activity, was able to inhibit the migration of CVB3-PPD immune mouse peritoneal exudate cells (IMPEC) as well as PEC from mice infected with CVB3 virus alone. Fraction II did not have antigenic activity as assessed by the agarose droplet cell migration inhibition assay. As controls, Fraction I prepared from the livers of spleens of CVB3-infected CD-1 mice was unable to inhibit the migration of CVB3 IMPEC. Unimmunized or "normal" mouse peritoneal exudate cells (NMPEC) were not inhibited by Fraction I. Antibodies prepared against Fractions I and II were unable to neutralize CVB3m virus in the plaque reduction test, and polyacrylamide gel analysis revealed multiple bands in 10% SDS gels.  相似文献   

17.
Guanylate cyclase activity is present in crude E. coli extract. Guanylate cyclase has been purified 3500 fold from this extract, through ammonium sulfate fractionation, DEAE-cellulose chromatography. Sephadex G-75 gel-filtration and polyacrylamide gel preparative microelectrophoresis. During the purification a guanylate cyclase inhibitor has been separated.  相似文献   

18.
Gorman DS  Levine RP 《Plant physiology》1966,41(10):1643-1647
Cytochrome 553 and ferredoxin were isolated and purified from acetone powders prepared from intact cells of the wild-type strain of Chlamydomonas reinhardi. Purification was achieved by ion exchange chromatography on DEAE cellulose and gel filtration on Sephadex G-75.  相似文献   

19.
During the days preceding the first ovulation the ovary of the rat exhibits a remarkable increase in estradiol (E2) and progesterone (P) release in response to gonadotropins. No such increase is observed in the case of androgens (A, testosterone + dihydrotestosterone). The present experiments were undertaken to examine the possibility of reproducing these developmental events by stimulating the ovary with a gonadotropin that has substantial FSH-like activity. In vivo administration of pregnant mare serum gonadotropin (PMSG) to juvenile 29-day-old rats greatly increased the in vitro E2 and A response to human chorionic gonadotropin (hCG) measured 2 days later in the morning. The magnitude of the A response was significantly larger than that of ovaries from juvenile animals or rats in first proestrus. The E2 response was much greater than that of juvenile ovaries but similar to that of ovaries from late proestrous rats. In contrast, the P response to hCG was not enhanced by PMSG. In fact the response was similar to that of juvenile ovaries and markedly less than that of first proestrous rats. This decreased P response was not due to a greater conversion of P to its less active metabolite 20 alpha-hydroxy-4-pregnen-3-one (20 alpha-OH-P). The results suggest that PMSG enhances the E2 and A response of immature ovaries to hCG at the expense of that of P. Treatment of immature rats with PMSG may represent a useful model to study E2 release from preovulatory ovaries, but it cannot be used to reproduce in its entirety the developmental changes in steroidal response to gonadotropins associated with normal puberty.  相似文献   

20.
Rats injected with aurothioglucose (ATG) for 5 days were subsequently injected with [75Se]selenious acid and killed after 3 days. Kidney and liver cytosols were chromatographed on Sephadex G-150. 75Se in kidney was associated with high molecular weight (HMW), 85,000 Mr, 26,000 Mr, and 10,000 Mr proteins and with a nonprotein fraction. The elution profile of liver cytosol was similar to that of kidney, but without a 26,000 Mr protein. ATG injection increased the association of 75Se with all fractions of kidney cytosol except the 85,000 Mr fractions, which contained Se-glutathione peroxidase (SeGSHPx) activity; 75Se in liver was increased only in HMW fractions. Unfractionated kidney cytosolic SeGSHPx activity was decreased 14% by ATG injection, but liver enzyme activity was not changed. However, Sephadex G-150 chromatography showed that total and specific activities, respectively, were decreased 28 and 23% in kidney and 25 and 16% in liver. Au coeluted with HMW and 10,000 Mr 73Se-containing kidney proteins; the latter contained 50% of the Au eluted from the column. DEAE Sephacel chromatography of the 10,000 Mr kidney protein showed that both Au and 75Se were tightly associated with metallothionein-like proteins. This study demonstrates the interaction of Au with rat liver and kidney 75Se-containing proteins.  相似文献   

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