Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 28
Filter
Add more filters










Publication year range
2.
Dev Biol Stand ; 98: 127-32; discussion 133-4, 1999.
Article in English | MEDLINE | ID: mdl-10494965

ABSTRACT

We have found that our MDCK-derived cell line (BV-5F1) is non-tumorigenic in tests conducted in accordance with FDA guidelines, and thus may be suitable for producing live, attenuated or inactivated vaccine. The cell line has been extensively tested for the presence of contaminating microorganisms. No infectious agents of viral or other microbial origin were present. Using the BV-5F1 cell line, we have now designed a process for the large-scale production of influenza virus for the manufacture of a vaccine. The production system involves expansion of cells anchored on a microcarrier using stirred fermenters, followed by virus infection. Viral particles are purified in a way similar to the licensed egg-derived vaccine Fluviral SF and mainly involves ultracentrifugation, ultrafiltration and formaldehyde inactivation. The final product is a split inactivated vaccine. A randomized, double-blind clinical study was made in healthy adults using the new split influenza vaccine derived from viruses grown in cell culture (bivalent formulation). The results of this Phase I study have demonstrated that the split influenza vaccine derived from cell culture is highly immunogenic and safe in adults.


Subject(s)
Influenza A virus/immunology , Influenza B virus/immunology , Influenza Vaccines/immunology , Adolescent , Adult , Cell Line , Consumer Product Safety , Double-Blind Method , Female , Humans , Male , Middle Aged , Virus Cultivation
3.
Can J Gastroenterol ; 13(2): 155-8, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10203436

ABSTRACT

Causes of a massive elevation in serum aminotransferases (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]) in the substance-abusing patient include viral hepatitis and drug hepatotoxicity. A patient chronically addicted to injection heroin and cocaine presented to the emergency room in a confused state and was admitted to a medical ward with an AST of 4120 U/L, ALT 3820 U/L and right upper quadrant discomfort. Investigations for viral and hepatotoxic causes for the liver dysfunction revealed only hepatitis C seropositivity. A computed tomogram of the abdomen, however, revealed a significant contusion to the right lobe of the liver consistent with traumatic injury. A motor vehicle accident, in which the patient was wearing a seat belt, and which had occurred a few days before admission and had been thought to be minor, was the cause of the liver dysfunction. Significant blunt abdominal traumatic injuries are usually managed exclusively by surgical trauma units. This case underlines the need for medical specialists to be aware of hepatic contusion injuries and to have a high index of suspicion when investigating unexplained hepatocellular dysfunction in chronic substance abusers who have been in motor vehicle accidents.


Subject(s)
Contusions/etiology , Hepatitis/etiology , Liver/injuries , Seat Belts/adverse effects , Substance-Related Disorders , Accidents, Traffic , Acute Disease , Humans , Transaminases/blood
4.
Cytotechnology ; 4(3): 261-9, 1990 Nov.
Article in English | MEDLINE | ID: mdl-1369301

ABSTRACT

Obligatory anchorage dependant Vero cells were successfully grown in gelatinous-like macrocarriers made of calcium alginate. Entrapped single cells were immobilized within the polymerized alginate matrix divide to form large spherical clumps of cells. A cell density of 17 x 10(6) cells/ml of alginate with over 95% viability was obtained after 14 days in spinner flasks. When subjected to poliovirus type I infection, spherical masses of Vero cells progressively showed extensive cytopathic effect but remained entrapped in the alginate matrix of the macrocarriers. Virus was released into a cellular debris free-like supernatant and reached a peak titer of 10(8.0) TCID50/ml after 72 hours.


Subject(s)
Cytological Techniques , Poliovirus/growth & development , Virus Cultivation/methods , Alginates , Animals , Cell Adhesion , Cell Count , Glucuronic Acid , Hexuronic Acids , Vero Cells
5.
J Virol Methods ; 25(1): 63-70, 1989 Jul.
Article in English | MEDLINE | ID: mdl-2476458

ABSTRACT

The growth of the murine coronavirus MHV-A59 on murine DBT cells adapted to dextran-made Cytodex 1 microcarriers was studied in comparison with cells grown on plastic dishes. With a microcarrier concentration of 5 g/l in spinner flasks, a density of 3 x 10(6) cells/ml was reached in 7 days. Under these conditions, cells supported virus growth to the same extent as when they were grown on the plastic substratum. This was shown by a similar development of virus-induced syncytia, the release of an equivalent number of infectious progeny virions per cell, similar recoveries observed after concentration and purification and an identical appearance of the purified virus under the electron microscope. On the other hand, the technical convenience of microcarriers and the ease of scale-up emphasize their potential for the growth of coronaviruses.


Subject(s)
Coronaviridae/growth & development , Culture Media , Dextrans , Virus Replication , Animals , Cell Division/drug effects , Cell Line/microbiology , Coronaviridae/isolation & purification , Coronaviridae/ultrastructure , Mice , Viral Plaque Assay
6.
Vet Microbiol ; 18(3-4): 219-31, 1988 Dec.
Article in English | MEDLINE | ID: mdl-2852870

ABSTRACT

Hemagglutination activity, structural protein profiles and neutralization assays were used in a comparative study of bovine herpesvirus 1 strains from the U.S.A., Canada, Great Britain, Denmark and Malaysia with equine, feline and human herpesviruses in order to further characterize the bovine herpesvirus 1 hemagglutinin. Bovine herpesvirus 1 strains of different geographical origins all showed hemagglutinating activity for mouse erythrocytes; furthermore, feline herpesvirus 1 was also shown to hemagglutinate mouse erythrocytes. Analyses of partly purified viruses showed that a distinctive and specific polypeptides profile is associated with each species of herpesviruses used in our study; strains of bovine herpesvirus 1 from North America, Europe and Southeast Asia however, presented a remarkable similarity as to their electrophoretic protein patterns. A protein similar to the 97-kDa bovine viral hemagglutinin was not identified with the hemagglutinating feline herpesvirus. An important neutralization epitope on the bovine viral hemagglutinin was also not found on feline, equine and human herpesviruses but was identified on all bovine strains tested from North America, Europe and Southeast Asia stressing the importance of the bovine hemagglutinin for eventual prophylactic purposes.


Subject(s)
Herpesviridae/classification , Herpesvirus 1, Bovine/classification , Herpesvirus 1, Equid/classification , Simplexvirus/classification , Animals , Antibodies, Monoclonal , Cats , Cattle , Electrophoresis, Polyacrylamide Gel , Hemagglutination, Viral , Hemagglutinins, Viral/analysis , Herpesviridae/analysis , Herpesviridae/immunology , Herpesvirus 1, Bovine/analysis , Herpesvirus 1, Bovine/immunology , Herpesvirus 1, Equid/analysis , Herpesvirus 1, Equid/immunology , Horses , Humans , Immunohistochemistry , Microscopy, Electron , Simplexvirus/analysis , Simplexvirus/immunology , Viral Proteins/analysis
7.
Vet Microbiol ; 13(2): 107-19, 1987 Feb.
Article in English | MEDLINE | ID: mdl-3031871

ABSTRACT

The immunogenicity of bovine herpesvirus type 1 (BHV-1) hemagglutinin has been investigated. Both live and nonionic detergent solubilized vaccines were prepared and 5000 hemagglutinating units (HAU) were injected subcutaneously into rabbits. Both types of vaccine induced a good antibody response but live virus was four times more efficient in inducing hemagglutination inhibiting and neutralizing antibodies than either Triton X-100- or octylglucoside-solubilized subunit vaccine. Blotting analysis revealed that five proteins, of 105,000, 90,000, 74,000, 64,000 and 54,000 mol. wt, were recognized by the serum of vaccinated animals. Triton X-100-solubilized vaccine did not induce antibodies against the 105,000 and 64,000 mol. wt proteins, indicating the important role of VP 90,000 and VP 74,000 in hemagglutination and neutralization. The order in which antibodies to the different viral proteins were induced was VP 90,000, (VP 105,000, VP 64,000, VP 54,000) and VP 74,000. Our data indicate that VP 90,000 is the hemagglutinin. Using convalescent serum from intranasally infected animals, we could identify nine structural proteins for BHV-1; VP 105,000, VP 90,000, VP 74,000, VP 64,000, VP 54,000, VP 50,000, VP 47,000, VP 40,000 and VP 31,000.


Subject(s)
Antibodies, Viral/biosynthesis , Herpesvirus 1, Bovine/immunology , Viral Proteins/immunology , Viral Vaccines/immunology , Animals , Enzyme-Linked Immunosorbent Assay , Hemagglutination Inhibition Tests , Hemagglutination Tests , Immunologic Techniques , Neutralization Tests , Rabbits , Viral Proteins/analysis
8.
J Virol ; 60(1): 302-6, 1986 Oct.
Article in English | MEDLINE | ID: mdl-2427748

ABSTRACT

The intracellular and structural polypeptides of the Los Angeles and Cooper 1 reference strains of bovine herpesvirus 1, together with 12 other Canadian field isolates, were analyzed by polyacrylamide gel electrophoresis. Although a few minor differences were noted among some isolates in regard to intracellular viral protein content, analysis of partly purified virus showed strikingly similar polypeptide profiles among 19 proteins with molecular masses of 14 to 145 kilodaltons (kDa). Moreover, a neutralizing monoclonal antibody produced against the Cooper 1 strain also neutralized all of the other 13 strains tested in this study and immunoprecipitated the major 90-kDa glycoprotein. A second monoclonal antibody with a high hemagglutination inhibition titer prevented hemagglutination of other strains tested and also reacted against the 90-kDa glycoprotein by immunoprecipitation, indicating that this glycoprotein is responsible for the hemagglutinating activity of the viral particle and carries an important neutralization epitope.


Subject(s)
Antigens, Viral/immunology , Hemagglutinins, Viral/immunology , Herpesvirus 1, Bovine/analysis , Antibodies, Monoclonal/immunology , Antibodies, Viral/immunology , Epitopes/immunology , Herpesvirus 1, Bovine/immunology , Neutralization Tests , Peptides/immunology
9.
Radiat Res ; 105(1): 76-83, 1986 Jan.
Article in English | MEDLINE | ID: mdl-3511495

ABSTRACT

Sheep antibodies to bovine type I collagen were employed in the immunohistochemical detection of type I collagen in lung tissue sections of irradiated LAF1 mice. A video image digitizing system was developed to estimate collagen levels, by assigning a numerical value (0-63) to each of approximately 53,800 picture elements (pixels) in the microscope field, according to the collagen-dependent fluorescence intensity at each locus. For lungs harvested 52 weeks subsequent to graded doses of 60Co gamma radiation between 0 and 10 Gy, a dose-dependent increase in type I collagen was observed in the alveolar walls. A reproducible increase was evident for doses as low as 5 Gy: doses of 7 to 10 Gy elicited type I collagen levels significantly elevated with respect to those of age-matched controls. These results are consistent with a role for type I collagen in the development of radiation-induced pulmonary fibrosis. The assay system developed here will be used to explore the role of connective tissue macromolecules in the development of radiation pneumonitis and fibrosis.


Subject(s)
Radiation Injuries/pathology , Animals , Cobalt Radioisotopes , Collagen/analysis , Fluorescent Antibody Technique , Gamma Rays , Lung/radiation effects , Male , Mice , Pulmonary Fibrosis/etiology , Pulmonary Fibrosis/pathology
10.
Can J Microbiol ; 32(1): 15-21, 1986 Jan.
Article in English | MEDLINE | ID: mdl-2421860

ABSTRACT

Immunovirological studies suggest that human respiratory syncytial virus may well be composed of five structural proteins as are other members of the Paramyxoviridae family: the two external membrane glycoproteins H (90 000) and Fo (F1, 49 000; F2, 20 000; disulfide linked), the internal membrane protein M (34 000), the nucleoprotein N (42 000), and a protein (78 000) designated P that could be the equivalent of the polymerase of the morbillivirus and paramyxovirus genus. Neutralizing monoclonal antibodies showed, by immunoprecipitation and immunoblotting, that the fusion protein carries neutralizing epitopes. One monoclonal antibody, which shows a high neutralizing titer, immunoblotted directly with the F1 fragment (49 000) of the fusion protein. Analysis in mice of the immunogenicity of the structural proteins separated on sodium dodecyl sulphate gels indicated that, under our conditions, only the fusion protein dimer Fo and its F1 fragment were capable of inducing neutralizing antibodies.


Subject(s)
Respiratory Syncytial Viruses/analysis , Viral Proteins/analysis , Animals , Antibodies, Monoclonal , Antibodies, Viral , Antibody Specificity , Capsid/analysis , Capsid/immunology , Epitopes/immunology , Fluorescent Antibody Technique , Guinea Pigs , Humans , Immunoelectrophoresis , Immunosorbent Techniques , Mice , Mice, Inbred BALB C , Neutralization Tests , Respiratory Syncytial Viruses/immunology , Viral Core Proteins/analysis , Viral Core Proteins/immunology , Viral Envelope Proteins/analysis , Viral Envelope Proteins/immunology , Viral Fusion Proteins , Viral Matrix Proteins , Viral Proteins/immunology
11.
Vet Microbiol ; 10(6): 517-23, 1985 Dec.
Article in English | MEDLINE | ID: mdl-3006322

ABSTRACT

Using C57BL/HPB mouse erythrocytes, hemagglutination has been observed with the Los Angeles and Colorado-1 strains of bovine herpesvirus type 1 and with 12 other Canadian field isolates as well. The specificity of the hemagglutination observed with the viral strains has been confirmed by a hemagglutination-inhibition assay.


Subject(s)
Hemagglutination, Viral , Herpesvirus 1, Bovine/immunology , Animals , Cattle , Hemagglutination Inhibition Tests , Hemagglutination Tests , Hemagglutinins, Viral , Mice
12.
Toxicol Appl Pharmacol ; 80(1): 147-54, 1985 Aug.
Article in English | MEDLINE | ID: mdl-4024102

ABSTRACT

The effects of postnatal methyl mercury exposure on the ontogeny of renal and hepatic responsiveness to trophic stimuli were examined. Increased ornithine decarboxylase (ODC) activity was used as an index of tissue stimulation. In the rat, renal ODC responsiveness to growth hormone, angiotensin, vasopressin, isoproterenol, and serotonin was absent at birth and matured 3 to 4 weeks later. However, pups exposed to methyl mercury showed marked, ODC responses to these same agents as early as 10 to 19 days of postnatal age, accompanied by a significant renal hypertrophy. In contrast to the kidney, the liver of normally developing rats was responsive to trophic factors even in the neonate. In this tissue, there was no consistent effect of neonatal methyl mercury treatment on ODC responses at any developmental stage tested; although absolute liver weights were reduced, liver/body weight ratio was not affected. These results demonstrate that postnatal methyl mercury exposure causes a precocious onset of ODC responses to trophic agents specifically in the kidney. Altered responsiveness may mediate some of the effects of this organomercurial on overall renal development and function.


Subject(s)
Animals, Newborn/metabolism , Kidney/drug effects , Liver/drug effects , Methylmercury Compounds/toxicity , Ornithine Decarboxylase/analysis , Animals , Female , Kidney/enzymology , Liver/enzymology , Male , Organ Size/drug effects , Pregnancy , Rats , Rats, Inbred Strains
13.
Neurotoxicology ; 5(4): 45-54, 1984.
Article in English | MEDLINE | ID: mdl-6097852

ABSTRACT

The effects of neonatal CH3-Hg exposure on development and function of peripheral catecholaminergic synapses were examined by measuring tissue norepinephrine (NE) levels and turnover rates and cardiac biochemical responses to sympathetic reflex stimulation. In the rat, cardiac sympathetic neurotransmission normally develops towards the end of the first week postnatally; however, pups given CH3-Hg showed responses to sympathetic reflex stimulation as early as 2 days of age. The accelerated maturation of cardiac sympathetic effect was accompanied by initial enhancement of NE levels and turnover. This effect appeared to be specific to the heart, as kidney displayed subnormal NE levels in CH3-Hg-treated animals. Since neonatal CH3-Hg produces heart and kidney overgrowth, we examined the potential role of sympathetic input in altered tissue growth, utilizing chemical sympathectomy with 6-hydroxydopamine (6-OHDA). Sympathectomy inhibited the early phase of renal overgrowth, suggesting that sympathetic nerves participate in the initial effect of CH3-Hg on this tissue; however, 6-OHDA did not influence later phases of renal enlargement nor did it alter the CH3-Hg-induced cardiac overgrowth. These results indicate that neonatal exposure to CH3-Hg alters the synaptic development of peripheral catecholamine neurons, which may play a role in some of the subsequent effects on tissue development.


Subject(s)
Cardiomegaly/chemically induced , Kidney Diseases/chemically induced , Methylmercury Compounds/toxicity , Sympathetic Nervous System , Animals , Catecholamines/metabolism , Heart/innervation , Hypertrophy , Kidney/innervation , Peripheral Nervous System Diseases/chemically induced , Rats , Rats, Inbred Strains
14.
J Virol Methods ; 7(3): 149-54, 1983 Sep.
Article in English | MEDLINE | ID: mdl-6643642

ABSTRACT

When analysed by polyacrylamide gel electrophoresis, human respiratory syncytial virus harvested after a one step growth cycle and purified through a continuous sucrose density gradient was shown to be composed of nine structural proteins of 90, 68, 49, 42, 34, 28, 25, 19 an 13 kd. The 90, 49 and 19 kd polypeptides were identified as glycopolypeptides by glucosamine incorporation. A modified immunoprecipitation procedure confirmed the viral specificity of the 49, 42, 28, 25 and 19 kd polypeptides.


Subject(s)
Glycoproteins/analysis , Respiratory Syncytial Viruses/analysis , Viral Proteins/analysis , Centrifugation, Density Gradient , Chemical Precipitation , Glycoproteins/isolation & purification , Humans , Polyethylene Glycols , Precipitin Tests , Viral Proteins/isolation & purification , Viral Structural Proteins
15.
Int J Dev Neurosci ; 1(1): 7-16, 1983.
Article in English | MEDLINE | ID: mdl-24875600

ABSTRACT

The role of ornithine decarboxylase (ODC) and the polyamines in development of central and peripheral catecholaminergic neurons was examined through the use of α-difluoromethylornithine (DFMO), a specific irreversible inhibitor of ODC. Short-term postnatal administration of DFMO (500 mg/kg daily on days 1-6) to neonatal rats resulted in effective inhibition of ODC and depletion of both putrescine and spermidine in brain, heart and kidney; after cessation of DFMO administration, polyamine levels returned to normal by 10-13 days of age. There were no signs of generalized toxicity of short-term DFMO treatment, as body weight gains were largely unaffected over the course of study (through weaning). However, development of peripheral sympathetic neurons was severely retarded by DFMO, with persistent and profound deficits of both cardiac and renal norepinephrine; the catecholamine deficiencies were unrelated to effects on end-organ growth, as cardiac weights were essentially normal whereas kidney weights were adversely affected by DFMO. Development of the adrenal medulla, a peripheral catecholaminergic tissue which displays approximately the same developmental profile as do sympathetic neurons but which does not develop axonal projections, was not slowed by DFMO treatment; similarly, central noradrenergic and dopaminergic neurons, which undergo the majority of axonal outgrowth and synaptogenesis during the second to third postnatal week (just after the period in which polyamines returned to control levels), developed normally as assessed by measurements of transmitter levels, tyrosine hydroxylase activity and synaptosomal uptake of [(3)H]norepinephrine or [(3)H]dopamine. Extension of the period of DFMO treatment and consequent depletion of polyamines into the period in which central synaptogenesis occurs does, however, produce slowing of development of brain catecholamine neuronal projections. Thus, the ODC/polyamine system appears to play a critical postnatal role in catecholamine systems specifically undergoing active synaptogenesis.

16.
Int J Dev Neurosci ; 1(2): 113-27, 1983.
Article in English | MEDLINE | ID: mdl-24875723

ABSTRACT

The roles of ornithine decarboxylase (ODC) and the polyamines in fetal and neonatal development were examined through the use of α-difluoromethylornithine (DFMO), a specific irreversible inhibitor of ODC. Administration to pregnant rats of 500 mg/kg of DFMO every 12 h for a 4-day period (8 DFMO injections) resulted in fetal and neonatal death; DFMO early in gestation produced fetal resorption whereas late gestational exposure did not compromise fetal viability but instead resulted in a delayed toxic effect, with high mortality in the first postnatal week. Generalized toxicity of DFMO was not apparent in later developmental periods, as 4 days of DFMO treatment begun postnatally did not produce any neonatal death. Shortening the course of gestational DFMO treatment to 2.5 days (5 DFMO injections) also did not adversely affect fetal or neonatal viability and thus permitted identification of critical periods in which various tissues are sensitive to DFMO. Examination of growth patterns of brain, heart and kidney and of neurochemical development of central and peripheral catecholaminergic neurons indicated that different critical periods exist for effects of DFMO on each tissue or even on the various cell types within a tissue. The separable sensitivities were apparent even though the effects of DFMO on ODC and the polyamines for any given treatment period were fairly uniform in all tissues studied. These results indicate that the ODC/polyamine system plays multiple roles in fetal survival and in tissue growth during discrete periods of development; because the time course of cellular maturation differs for each tissue or cell population, DFMO administered during any one brief period can produce organ-specific developmental deficits.

17.
Toxicol Lett ; 13(3-4): 267-76, 1982 Oct.
Article in English | MEDLINE | ID: mdl-7147271

ABSTRACT

To determine the organ specificity of neonatal mercury hydroxide (CH3HgOH) exposure on biochemical development of its potential target tissues, effects on rat brain, liver, heart and kidney were compared utilizing the ontogenetic pattern of ornithine decarboxylase (ODC) activity, an early index of perturbation of cellular maturation. CH3HgOH was given daily beginning at birth for up to 21 days, using three dose levels (1, 2.5 or 5 mg/kg s.c.). In the brain, CH3HgOH treatment resulted in an initial reduction in ODC followed by a subsequent elevation of activity, a maturational pattern known to be associated with delayed cellular development. In contrast to the effects of CH3HgOH on brain, the pattern obtained in the liver, an initial elevation followed by a subsequent decline, is usually associated with compression of the time couse of cellular development. In the heart and kidney, CH3HgOH produced sustained elevations of ODC representing prolongation of the developmental period of rapid tissue growth and development; these patterns were associated with tissue hypertrophy which was sustained through the preweaning stage for both tissues and well into the postweaning period for the kidney. The results obtained with ODC clearly demonstrate that neonatal CH3HgOH poisoning causes organ-specific biochemical lesions which can play a role in subsequent effects on overall tissue development.


Subject(s)
Animals, Newborn/metabolism , Carboxy-Lyases/metabolism , Methylmercury Compounds/poisoning , Ornithine Decarboxylase/metabolism , Aging , Animals , Female , Organ Size/drug effects , Organ Specificity , Pregnancy , Rats , Rats, Inbred Strains
18.
J Pharmacol Exp Ther ; 222(3): 741-5, 1982 Sep.
Article in English | MEDLINE | ID: mdl-6809932

ABSTRACT

To evaluate the role of ornithine decarboxylase (ODC) and the polyamines in tissue growth and development, neonatal rats were given daily injections of alpha-difluoromethylornithine, a specific, irreversible inhibitor of ODC. Enzyme activity in brain, heart and kidney was effectively inhibited, leading to prompt reductions in putrescine levels which were apparent throughout the 4-week period of drug treatment. Deficits in spermidine levels appeared within several days and remained significant in all three tissues, although some recovery toward control levels was apparent after 2 weeks postnatally. Spermine levels were not decreased and in some cases were actually increased during the course of alpha-difluoromethylornithine administration; assessment of total organ content of spermine or total polyamines per organ (putrescine + spermidine + spermine) indicated that the tissues were still actively increasing their net polyamine content despite continued inhibition of ODC. Growth of the kidney and brain were affected within several days of commencing alpha-difluoromethylornithine treatment, well before the onset of body weight or heart weight deficits. By 14 days of age and thereafter, animals displayed delayed eye-opening, deficient fur growth and shorter body length. These data suggest that the ODC/polyamine system does serve as a modulator of tissue growth during neonatal mammalian development and that differences exist among various tissues in the degree and time course of dependence of growth on polyamines, particularly putrescine and/or spermidine.


Subject(s)
Animals, Newborn/growth & development , Carboxy-Lyases/antagonists & inhibitors , Carboxy-Lyases/physiology , Ornithine Decarboxylase Inhibitors , Ornithine Decarboxylase/physiology , Ornithine/analogs & derivatives , Polyamines/pharmacology , Animals , Brain/enzymology , Brain/growth & development , Eflornithine , Female , Heart/growth & development , Kidney/enzymology , Kidney/growth & development , Myocardium/enzymology , Ornithine/pharmacology , Pregnancy , Putrescine/pharmacology , Rats , Rats, Inbred Strains , Spermidine/pharmacology , Spermine/pharmacology
19.
J Pharmacol Exp Ther ; 222(3): 746-51, 1982 Sep.
Article in English | MEDLINE | ID: mdl-6125588

ABSTRACT

Daily administration of alpha-difluoromethylornithine (DFMO) to neonatal rats results in persistent inhibition of ornithine decarboxylase, depletion of polyamines and rapid onset of brain growth deficits. Animals treated with DFMO displayed marked retardation of synaptic development of catecholaminergic systems in the brain, evidenced by slowed development of synaptosomal uptake of [3H]norepinephrine and of tyrosine hydroxylase activity. Fundamental alterations in brain membrane metabolism also could be detected through measurements of phospholipid incorporation of 33Pi; DFMO suppressed the developmental increments in phospholipid synthesis normally accompanying synaptic outgrowth. Although the content of norepinephrine and dopamine in the brain was unchanged by DFMO, the drug did cause initial reductions, and subsequent elevations, in catecholamine turnover. Effects of DFMO on development of peripheral sympathetic neurons were even more profound, with substantial deficits in norepinephrine content throughout preweanling development, again accompanied by biphasic alterations of turnover. The adrenal medulla, a sympathetic tissue which does not undergo catecholaminergic axonal outgrowth and synaptogenesis, was spared the deleterious effects of DFMO on development. These results support the view that ornithine decarboxylase and the polyamines play an obligatory role in synaptic maturation, with the greatest sensitivity to DFMO-induced alterations occurring during periods of rapid development.


Subject(s)
Animals, Newborn/growth & development , Brain/drug effects , Carboxy-Lyases/antagonists & inhibitors , Ornithine Decarboxylase Inhibitors , Ornithine/analogs & derivatives , Sympathetic Nervous System/drug effects , Animals , Brain/growth & development , Dopamine/metabolism , Eflornithine , Female , Neurons/drug effects , Neurotransmitter Agents , Norepinephrine/metabolism , Ornithine/pharmacology , Ornithine Decarboxylase/physiology , Polyamines/pharmacology , Pregnancy , Rats , Rats, Inbred Strains , Receptors, Neurotransmitter/drug effects , Tyrosine 3-Monooxygenase/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...