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Query: UMLS:C0155339 (Brown)
 12,436 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A hyperacute form of experimental autoimmune encephalomyelitis (HEAE) was induced in Lewis rats using small doses (3.2 mug) of guinea pig myelin basic protein as immunogen and B. pertussis vaccine as adjuvant. Myelin basic proteins from species other than guinea pig (rat, man, monkey, pig, ox, rabbit and sheep) induced only ordinary EAE with this adjuvant. HEAE was more readily distinguished from ordinary EAE by clinical criteria (early onset, with a rapid and severe course, and high incidence of cerebral signs and mortality) than by histologic signs which, although characteristic of HEAE. were not pathognomonic for HEAE, HEAE was transferred to x-irradiated syngeneic recipient rats with lymph node cells from appropriately immunized donors. The Brown Norway (BN) strain of rat was found susceptible to induction of ordinary EAE, but not HEAE, using large doses of either rat or guinea pig myelin basic proteins. The unique immunogenicity of the guinea pig basic protein must be due to a different antigenic determinant from the determinant(s) which is shared by rat and guinea pig myelin basic proteins and which without B. pertussis induces ordinary EAE. The adjuvant action of B. pertussis in inducing HEAE in the Lewis rat is most likely mediated through an immunocompetent T lymphocyte.
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PMID:Antigen, host and adjuvant requirements for induction of hyperacute experimental autoimmune encephalomyelitis. 6 74

Brown Norway (BN) rats are much less susceptible to experimental allergic encephalomyelitis (EAE) than Lewis rats. Nevertheless, BN rats developed severe EAE, even paralysis, when immunized with rat spinal cord and carbonyl iron adjuvant. Complete Freund's adjuvant (CFA) was much less effective. The use of both CFA and pertussis vaccine with rat cord was moderately, but not consistently, effective. Guinea pig spinal cord was weakly encephalitogenic to BN rats with all adjuvant combinations. We were not able to produce EAE in BN rats with purified myelin basic protein from either rat or guinea pig. Inoculations directly into lymph nodes or into the blood stream proved that the low susceptibility of BN rats was not due to lack of absorption from the site of inoculation, but may be related to peculiarities of processing antigen in draining lymph nodes. The severity of EAE in F1 hybrids was intermediate between the BN and Lewis parental strains when tested with an immunizing procedure of appropriate strength. The fact that F1 hybrids were less reactive than Lewis mandates modification of the theory that susceptibility to EAE is inherited through a single autosomal dominant gene.
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PMID:Allergic encephalomyelitis in the reputedly resistant Brown Norway strain of rats. 112 Sep 1

The purpose of the study was to examine the effect of ketotifen on the airway responses and the recruitment of the inflammatory cells into the airways of sensitized rats after antigen challenge. Twenty-five Brown Norway rats, 7-9 weeks old, were actively sensitized to ovalbumin (OA) (1 mg s.c.) and Bordetella pertussis vaccine (10(9) bacilli i.p.). At 14 days after sensitization rats were anesthetized with urethane (1.1 g/kg i.p.) and intubated endotracheally. Aerosols of OA (5% W/V in saline for 5 min) were administered to control rats (Group A; n = 9), to a low-dose ketotifen group (Group B; 1 mg/kg PO; n = 8) and a high-dose ketotifen group (Group C; 10 mg/kg; PO for 10 days; n = 9). Pulmonary resistance (RL) was measured at baseline, and every 15 min for up to 8 h after OA. The magnitude of the early response was 241 +/- 51% in A (% baseline RL; mean +/- SE), and significantly less in B(119 +/- 7%) and C(131 +/- 16%) (p < 0.01). The late response was significantly lower in C than A but not B. The total cell number in bronchoalveolar lavage at 8 h after OA challenge was significantly higher in A than B and C (p < 0.01). The lymphocyte and eosinophil counts were reduced in B and C compared to A (p < 0.05). A positive correlation was found between the late response and total number of cells recovered in the BAL (r = 0.78) (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of ketotifen on airway responses to allergen challenge in the actively sensitized brown Norway rat. 129 73

The aim of this study was to examine the relationships between allergen-induced early and late airway responses and antigen-specific IgE, IgG, and lymphocyte subsets in blood and bronchoalveolar lavage (BAL). Brown Norway rats were sensitized at 7 weeks of age with ovalbumin (1 mg s.c.) with use of Bordetella pertussis as an adjuvant. Three weeks after sensitization, animals were anesthetized and challenged with an aerosol of ovalbumin (5% wt/vol in saline) for 5 minutes. Each animal was studied for 8 hours with repeated measurements of lung resistance. Blood was obtained at 0, 1, 2, and 3 weeks before ovalbumin challenge. Ovalbumin-specific IgE and IgG were determined by ELISA. No specific antibody was detectable before sensitization. Ovalbumin-specific IgE and IgG rose between 1 to 2 weeks after sensitization and peaked at 3 weeks. The IgE level did not correlate with the magnitude of either the early or the late responses. In a similar manner no correlation existed between the magnitude of specific IgG and the late response. However, a significant inverse correlation (r = -0.73; p < 0.01) occurred between specific IgG and the early response. No correlation occurred between the ratio of helper (W3/25 +) to suppressor (OX-8 +) lymphocytes in blood and BAL and airway responses to allergen. The size of the early and late responses were correlated, suggesting a common stimulus. Despite the blunting of the early response by repeated sensitization the late response was unaffected, suggesting that the factors that determine the physiologic expression of the early and late responses are different.
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PMID:The relationship between late asthmatic responses and antigen-specific immunoglobulin. 138 8

The purpose of the study was to investigate the relationships between upper airways responses and pulmonary responses of two strains of highly inbred rats to inhaled antigen. To do this we measured the upper and lower airways resistance for 60 min after challenge of Brown-Norway rats (BN; n = 13) and an inbred rat strain (MF; n = 11), derived from Sprague-Dawley, with aerosolized ovalbumin (OA). Rats were actively sensitized with OA (1 mg sc) using Bordetella pertussis as an adjuvant. Two weeks later the animals were anesthetized and challenged. Tracheal pressure, esophageal pressure, and airflow were measured, from which total pulmonary resistance was partitioned into upper airway and lower pulmonary resistance (RL). The peak upper airway response to inhaled OA was similar in BN (1.89 +/- 0.66 cmH2O.ml-1.s; n = 7) and MF (2.85 +/- 0.68 cmH2O.ml-1.s; n = 6). The lower airway response to OA challenge was substantially greater in BN, and RL changed from 0.07 +/- 0.01 to 0.34 +/- 0.13 (n = 6; P < 0.05). The MF did not have any significant increase in RL after challenge; the baseline RL was 0.12 +/- 0.02 and only reached a peak value of 0.15 +/- 0.05 (n = 5; P = NS). Lower airway responsiveness of BN (n = 10) to serotonin, an important mediator early allergic airway responses, was similar to MF (n = 7).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Comparison of upper and lower airway responses of two sensitized rat strains to inhaled antigen. 144 11

Exposure of non-sensitized Brown Norway (BN) rats to a 10%-ovalbumin aerosol induced an increase in the number of neutrophils in the broncho-alveolar lavage (BAL) fluid 3 and 6 h later but with no change in number of cells at 24 h. When the BN rats were actively sensitized (i.m. injection of 10 mg/kg ovalbumin and i.p. injection of killed Bordetella pertussis) and exposed 12-14 days later to a 10%-ovalbumin aerosol there was an increase in the number of eosinophils in the BAL fluid, maximal 24-48 h after the anaphylactic reaction. The increase in the number of neutrophils in the bronchial lumen 3 and 6 h after the anaphylactic reaction was larger than that obtained in non-specific inflammation and in contrast to this was still present 24-48 h after ovalbumin exposure. In passively sensitized BN rats exposed to ovalbumin aerosol, no inflammation appeared in the BAL fluid 24 h after the anaphylactic reaction. Various drugs, administered twice, 5 min and 5 h after the anaphylactic reaction, have been evaluated for their effects on the 24-h inflammation obtained in actively sensitized rats. Dexamethasone acetate (0.08 mg/kg i.p.) and theophylline (50 mg/kg i.p.) decreased the number of eosinophils and neutrophils. Ketotifen fumarate (12.5 mg/kg), cetirizine dihydrochloride (12.5 mg/kg), salbutamol (2 mg/kg), disodium cromoglycate (50 mg/kg) all given intraperitoneally, reduced the number of eosinophils. Tioxamast decreased the number of eosinophils at 12.5 mg/kg i.p. and by the oral route.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Model of bronchial allergic inflammation in the brown Norway rat. Pharmacological modulation. 151 77

The signal transduction mechanisms involved in the regulation of phagocytosis are largely unknown. We have recently shown that in neutrophils, when IgG-mediated phagocytosis is stimulated by formyl-methionyl-leucyl-phenyl-alanine (fMLP), the enhanced ingestion is dependent on the increase in [Ca2+]i which results from ligation of Fc receptors by the IgG-coated target (Rosales, C., and Brown, E. (1991) J. Immunol. 146, 3937-3944). Now, we have studied the mechanism by which this rise in [Ca2+]i occurs. Aggregated IgG, the monoclonal antibody 3G8 (which recognizes Fc receptor type III), and insoluble immune complexes caused an increase in [Ca2+]i. The rise in [Ca2+]i induced by Fc receptor ligation was resistant to pertussis toxin. In contrast, fMLP induced a rise in [Ca2+]i which was inhibited by pertussis toxin. fMLP-induced [Ca2+]i was accompanied by an accumulation of inositol 1,4,5-trisphosphate (IP3) which peaked by 15 s, and which was also abolished by pertussis toxin. IP3 accumulation after aggregated IgG, 3G8, or insoluble immune complexes was much less than after fMLP. Unlike [Ca2+]i rise induced by Fc receptor ligation, this small increase in IP3 was inhibited by pertussis toxin. These data demonstrated that the [Ca2+]i increase induced by Fc receptor ligation is not mediated by IP3. Immediate pretreatment of human polymorphonuclear neutrophils with optimal doses of fMLP also reduced subsequent increase in [Ca2+]i rise from thapsigargin, a sesquiterpene lactone tumor promoter that releases intracellular Ca2+ from IP3-sensitive stores without IP3 turnover. Similarly, to its effects on thapsigargin, fMLP inhibited the [Ca2+]i rise upon subsequent immune complex binding. Pretreatment of cells with immune complexes also prevented subsequent [Ca2+]i rise from thapsigargin and fMLP. These data demonstrate that IgG Fc receptor ligation and fMLP activation of human polymorphonuclear neutrophils use distinct signal transduction mechanisms to release Ca2+ from the same thapsigargin-sensitive intracellular pool. In contrast to fMLP, signal transduction for increased [Ca2+]i after Fc receptor stimulation does not involve a pertussis toxin-sensitive G protein, and is independent of IP3.
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PMID:Signal transduction by neutrophil immunoglobulin G Fc receptors. Dissociation of intracytoplasmic calcium concentration rise from inositol 1,4,5-trisphosphate. 153 82

Brown-Norway rats (male) were sensitized with both dinitrophenylated-bovine serum albumin (DNP-BSA) and Bordetella pertussis simultaneously in order to induce airway hyperresponsiveness (AHR) as the first sensitization. At five days, DNP-BSA was inhaled as a booster into the airways under thiopental anaesthesia. At eight days, inhalation of antigen markedly increased the tracheal pressure (TP) in sensitized rats (11.9 +/- 1.6 cmH2O) and slightly increased TP in non-sensitized rats (1.1 +/- 0.4), the difference between the two groups being significant (p less than 0.001). Twenty-four hours after antigen challenge, the airway responsiveness to ACh in sensitized rats was markedly increased to about 4-fold as compared to that in non-sensitized rats. Inhalation of dinitrophenylated-ovalbumin failed to increase the airway responsiveness to ACh in rats sensitized with DNP-BSA, although a marked increase in TP was induced immediately after antigen challenge. We thus succeeded in preparing a model of AHR by employing a new procedure of sensitization.
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PMID:Induction of airway hyperresponsiveness in allergic rats. 171 32

In Brown Norway (BN) rats, it is known to be difficult to induce experimental autoimmune uveoretinitis (EAU) by the injection of retinal S-antigen (S-Ag) or interphotoreceptor retinoid-binding protein (IRBP) together with complete Freund's adjuvant (CFA), unless intravenous Bordetella Pertussis is used as an additional adjuvant. In the present study it was found that the rate of onset of EAU could be increased in BN rats immunized with IRBP and CFA by simultaneous cryosurgery to the renal cortex. There was no evidence of retinal vasculitis, pinealitis or nephritis in the rats with EAU except for renal inflammatory infiltrates as a reaction to the cryosurgery. Affected eyes eventually showed destruction of most retinal components and prominent infiltration of the retina by macrophages, with the changes being more severe than those previously reported in Lewis rats with EAU induced by IRBP. Data suggesting the existence of an antibody that cross-reacts with the proximal renal tubules and the retinal pigment epithelium were also obtained.
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PMID:Experimental autoimmune uveoretinitis in brown Norway rats induced by bovine interphotoreceptor retinoid-binding protein and renal cryosurgery. 189 71

The beta gamma subunits of G-proteins are composed of closely related beta 35 and beta 36 subunits tightly associated with diverse 6-10 kDa gamma subunits. We have developed a reconstitution assay using rhodopsin-catalyzed guanosine 5'-3-O-(thio)triphosphate (GTP gamma S) binding to resolved alpha subunit of the retinal G-protein transducin (Gt alpha) to quantitate the activity of beta gamma proteins. Rhodopsin facilitates the exchange of GTP gamma S for GDP bound to Gt alpha beta gamma with a 60-fold higher apparent affinity than for Gt alpha alone. At limiting rhodopsin, G-protein-derived beta gamma subunits catalytically enhance the rate of GTP gamma S binding to resolved Gt alpha. The isolated beta gamma subunit of retinal G-protein (beta 1, gamma 1 genes) facilitates rhodopsin-catalyzed GTP gamma S exchange on Gt alpha in a concentration-dependent manner (K0.5 = 254 +/- 21 nM). Purified human placental beta 35 gamma, composed of beta 2 gene product and gamma-placenta protein (Evans, T., Fawzi, A., Fraser, E.D., Brown, L.M., and Northup, J.K. (1987) J. Biol. Chem. 262, 176-181), substitutes for Gt beta gamma reconstitution of rhodopsin with Gt alpha. However, human placental beta 35 gamma facilitates rhodopsin-catalyzed GTP gamma S exchange on Gt alpha with a higher apparent affinity than Gt beta gamma (K0.5 = 76 +/- 54 nM). As an alternative assay for these interactions, we have examined pertussis toxin-catalyzed ADP-ribosylation of the Gt alpha subunit which is markedly enhanced in rate by beta gamma subunits. Quantitative analyses of rates of pertussis modification reveal no differences in apparent affinity between Gt beta gamma and human placental beta 35 gamma (K0.5 values of 49 +/- 29 and 70 +/- 24 nM, respectively). Thus, the Gt alpha subunit alone does not distinguish among the beta gamma subunit forms. These results clearly show a high degree of functional homology among the beta 35 and beta 36 subunits of G-proteins for interaction with Gt alpha and rhodopsin, and establish a simple functional assay for the beta gamma subunits of G-proteins. Our data also suggest a specificity of recognition of beta gamma subunit forms which is dependent both on Gt alpha and rhodopsin. These results may indicate that the recently uncovered diversity in the expression of beta gamma subunit forms may complement the diversity of G alpha subunits in providing for specific receptor recognition of G-proteins.
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PMID:Rhodopsin and the retinal G-protein distinguish among G-protein beta gamma subunit forms. 190 16


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