Inflammatory mediators and cellular infiltration of the lungs in a guinea pig model of the late asthmatic reaction.

Alterations in cell numbers, vascular permeability, and concentrations of various inflammatory mediators in the lung were measured in a guinea pig model of the late asthmatic reaction. Animals sensitized by inhalation of ovalbumin were challenged with an aerosol of ovalbumin or saline, and bronchoalveolar lavage fluid (BALF) and peripheral blood were collected after periods ranging from 5 min to 72 h. Increased vascular leakage within the lungs was indicated by elevated BALF/plasma albumin ratios at all time points, and was maximal 6 h after challenge.

Long term effects of prenatal cocaine exposure on bone in rats.

Prenatal exposure to cocaine has been shown to produce a variety of effects on skeletal development and mineralization in humans, mice, and rats. The effects of cocaine on bone cell function and mineral metabolism pre- and postnatally are poorly understood. The present study examined the long term effects of prenatal cocaine exposure on femoral growth and mineralization in male rats.

Mediator secretion from human skin mast cells provoked by immunological and non-immunological stimulation.

Mast cells of the human skin not only release mediators following immunological activation, but may also be stimulated to release histamine by the neuropeptides substance P, vasoactive intestinal polypeptide and somatostatin or by other basic secretagogues such as morphine, poly-L-lysine and compound 48/80. Release of histamine under these conditions is rapid and accompanied by minimal generation of the eicosanoids, prostaglandin (PG)D2 and leukotriene (LT)C4. Transient elevations of intracellular calcium are associated with mediator secretion induced by both stimuli, that induced by anti-IgE being derived from extracellular sources through channels in the plasma membrane while that stimulated by neuropeptides is mobilized intracellularly.

Neuropeptide-induced secretion from human skin mast cells.

Unlike human mast cells associated with mucosal surfaces such as lung, adenoids, tonsils and intestine, skin mast cells may be stimulated to release histamine by the neuropeptides substance P, vaso-active intestinal polypeptide and somatostatin or by other basic secretagogues such as morphine and compound 48/80. Release of histamine by neuropeptides is rapid and accompanied by minimal generation of the eicosanoids prostaglandin D2 and leukotriene C4. Transient elevations of intracellular calcium are associated with mediator secretion induced by both immunological and non-immunological stimulation, that induced by anti-IgE being derived from extracellular sources through channels in the plasma membrane while that stimulated by neuropeptides is mobilized intracellularly.

Mast cell numbers and staining characteristics in the normal and allergic human conjunctiva.

In this study we report the numbers and metachromatic dye-staining characteristics of mast cells (MCs) in the conjunctiva of normal subjects and patients with seasonal allergic conjunctivitis caused by pollenosis. In addition, we have used a monoclonal antibody to the MC-specific enzyme, tryptase, to enumerate tryptase-positive cells immunohistochemically. Tarsal conjunctival MCs were found to be present in increased numbers in the allergic compared to the nonallergic subjects.

Studies of cellular mechanisms for the generation of superoxide by guinea-pig eosinophils and its dissociation from granule peroxidase release.

Guniea-pig peritoneal eosinophils generated superoxide anions in response to opsonized zymosan, platelet activating factor, sodium fluoride, digitonin, phorbol ester and calcium ionophore, but were refractory to fMLP. These agonists did not stimulate release of eosinophil peroxidase. The phospholipase inhibitor, mepacrine, and the protein kinase inhibitor, trifluoperazine, were effective inhibitors of superoxide production.

Corticosteroid treatment reduces mast cell numbers in inflammatory bowel disease.

Mast cell degranulation in the gut causes mucus secretion, mucosal edema, and increased gut permeability and may be responsible for some of the symptoms and signs of inflammatory bowel disease. We have used a novel monoclonal antibody (AAI) against tryptase expressed exclusively in the granules of mast cells to enumerate mast cells in rectal biopsies in order to study the effect of inflammatory bowel disease and drug treatment upon rectal mast cell numbers. Rectal mast cell numbers are significantly reduced in inflammatory bowel disease patients taking corticosteroids (mean 4.

Immunohistochemical identification of mast cells in formaldehyde-fixed tissue using monoclonal antibodies specific for tryptase.

An avidin-biotin enhanced immunoperoxidase procedure using monoclonal antibodies (AA1, AA3, and AA5) prepared against human mast cell tryptase resulted in intense staining of mast cells in paraffin-embedded tissue. The distribution of mast cells observed was similar to that seen when adjacent serial sections were stained using a standard procedure with toluidine blue, though the immunoperoxidase technique permitted the identification of significantly more mast cells. With monoclonal antibody AA1, immunostaining was entirely specific for mast cell granules, and there was negligible background staining in a range of tissues including lung, tonsil, colon, gastric mucosa, skin, and pituitary.

Dissociated human foreskin mast cells degranulate in response to anti-IgE and substance P.

Human skin mast cells release histamine in response to both immunologic stimulation mediated by anti-IgE and IgE-independent mechanisms of which substance P is a prototypical secretagogue. We compared the ultrastructural changes produced in dissociated foreskin mast cells by these two stimuli with histamine release. Mast cells were isolated and pooled from the foreskins of 2- to 7-year-old boys in four separate experiments and comprised 25 to 60% of the total dissociated cells.

Production and characterization of monoclonal antibodies specific for human mast cell tryptase.

Human mast cell tryptase was purified from lung tissue by high salt extraction, ammonium sulphate precipitation, octyl Sepharose and heparin-agarose chromatography. The tryptase isolated was a tetramer with a molecular weight of 132 kD on gel filtration, and on SDS-polyacrylamide gel electrophoresis was reduced to a single diffuse band with a mean molecular weight of 32.5 kD.

A health promotion module for undergraduate medical students.

This paper describes a 4-day module on health promotion which is part of the undergraduate programme for medical students at the University of Edinburgh. Early experience of the module from both the learner and teacher perspectives are reported. The module is part of a new 4-week course on community medicine for fourth- and fifth-year students and is a collaborative venture between people working in the field of health promotion in the University, the local health service and the national health education organization, the Scottish Health Education Group.

Prenatal cocaine exposure in the Long-Evans rat: III. Developmental effects on the brainstem auditory-evoked potential.

Prenatal cocaine exposure has been associated with a variety of adverse neurological effects in infants and laboratory animals. Of particular interest, one group of investigators reported that exposed neonates have an abnormality in the brainstem auditory-evoked potential (BAEP). The particular abnormality, a prolongation in the wave I-V interpeak latency, suggested delayed or desynchronized transmission of subcortical auditory information.

Prenatal cocaine exposure in the Long-Evans rat: II. Dose-dependent effects on offspring behavior.

Pregnant Long-Evans rats were injected daily with 40, 60, 80 or 100 mg/kg cocaine HCl (SC, 2% solution) from gestational days 7-20 (sperm positive = day 0). Daily doses were split with half given between 9:00-10:00 a.m.

Prenatal cocaine exposure in the Long-Evans rat: I. Dose-dependent effects on gestation, mortality, and postnatal maturation.

Pregnant Long-Evans rats were injected daily with 40, 60, 80, or 100 mg/kg cocaine HCl (SC, 2% solution) from gestational days 7-20 (sperm positive = day 0). Daily doses were split evenly with half given between 9:00-10:00 a.m.

Platelet activating factor does not release histamine from human dispersed cutaneous mast cells.

Histamine H1-antagonists inhibit the weal-and-flare responses to the intradermal injection of platelet activating factor (PAF) in humans, and PAF response is reduced in histamine-depleted skin sites. This indicates that mast cell histamine release is likely to be the mechanism of this response. We have therefore studied the interaction of PAF with cutaneous mast cells by observing whether it releases histamine directly from human dispersed foreskin mast cells, potentiates the activity of known mast cell stimulants or liberates histamine releasing factors (HRFs) from human platelets and leucocytes to release mast cell histamine by an indirect mechanism.

Evidence for thromboxane receptor mediated contraction of guinea-pig and human airways in vitro by prostaglandin (PG) D2, 9 alpha,11 beta-PGF2 and PGF2 alpha.

The rank orders of potency of prostaglandin D2, prostaglandin F2 alpha, 9 alpha,11 beta-prostaglandin F2 and the stable thromboxane A2 mimetics U-46619 and ONO-11113 were determined in guinea-pig trachea and human bronchus in vitro. In both tissues the thromboxane mimetics were markedly more potent than the other prostanoids with EC50 values in the nanomolar range. The prostanoid antagonists BW-245C, EP-092 and GR-32191 attenuated the contractile responses to all of the prostanoid agonists and TXA2 mimetics tested in guinea-pig tracheal spirals, although agonist selectivity was seen.

Maternal age and blood alcohol concentration in the pregnant Long-Evans rat.

Despite comparable alcohol consumption, not all women who drink excessively give birth to children with fetal alcohol effects or the fetal alcohol syndrome. Various maternal factors may be important in this regard. For example, two recent animal studies found that maternal age was an important risk factor in regard to alcohol's adverse effects on pregnancy.

Evidence that neutrophils do not participate in the late-phase airway response provoked by ovalbumin inhalation in conscious, sensitized guinea pigs.

Inhalation of ovalbumin by conscious, sensitized guinea pigs induced two phases of airway obstruction measured at 2 h (EAR) and at 17 h (LAR), respectively. In addition to causing airway obstruction, allergen challenge induced an accumulation in the bronchial lumen of eosinophil and neutrophil polymorphonuclear leukocytes at 17 h. Intraperitoneal injection of guinea pigs with a specific rabbit anti-guinea pig neutrophil serum 24 h before challenge reduced the number of circulating neutrophils by 94% and the airway neutrophilia after challenge by 90%, but it had no effect on the magnitude of either the EAR or the LAR.

T lymphocytes and eosinophils in allergen-induced late-phase asthmatic reactions in the guinea pig.

The kinetics and phenotype of T lymphocytes infiltrating the airways of guinea pigs undergoing late-phase asthmatic reactions (LAR) were studied with monoclonal antibodies, cytofluorimetry, and immunocytochemistry. Challenge of sensitized animals with aerosolized ovalbumin was followed by early (2 h) and late-phase (17 h) bronchoconstriction. The induction of hypersensitivity, by aerosolized antigen, was associated with an increase in mucosal T cell numbers, which consisted almost entirely of CD8+ T cells.

The response of plasma histamine to bronchoprovocation with methacholine, adenosine 5'-monophosphate, and allergen in atopic nonasthmatic subjects.

To investigate the possible role of mast cell histamine release in mediating adenosine 5'-monophosphate (AMP)-induced bronchoconstriction, we have measured the histamine concentration in peripheral venous plasma following inhalation of methacholine, AMP, and allergen in concentrations sufficient to provoke mean maximum decreases in FEV1 of 42.8 +/- 2.2%, 46.

Adenosine bronchoconstriction in asthma: investigations into its possible mechanism of action.

1. Inhaled adenosine and its parent nucleotide, adenosine 5'-monophosphate (AMP) provoke bronchoconstriction in atopic and asthmatic individuals but not in normal subjects. 2.

Histochemical heterogeneity of human mast cells: disease-related differences in mast cell subsets recovered by bronchoalveolar lavage.

Fixation and staining characteristics were studied for mast cells recovered by bronchoalveolar lavage from 67 patients being investigated for lung disease. The number of toluidine blue stained mast cells in formaldehyde-fixed cytocentrifuge preparations was consistently less than in specimens fixed in Carnoy's solution, though the counts were highly dependent on the period of fixation or staining. The cellular histamine content closely correlated with total mast cell numbers in bronchoalveolar lavage fluid, but was not related to the relative proportions of mast cells which were sensitive or resistant to formaldehyde fixation when using a standard protocol.

The inhibitory actions of azelastine hydrochloride on the early and late bronchoconstrictor responses to inhaled allergen in atopic asthma.

We have examined the effect of azelastine hydrochloride, 8.8 mg, on the early and late responses to inhaled allergen in a group of 12 atopic subjects with asthma. On two separate days, 3 weeks apart, patients were administered either oral azelastine, 8.

The IgE- and calcium-dependent release of eicosanoids and histamine from human purified cutaneous mast cells.

Cells dispersed from human foreskin were passively sensitized with IgE and then depleted or enriched in mast cells by density gradient centrifugation. Arachidonic acid metabolism was initially studied by radio-high-performance liquid chromatography analysis of incubation media from cells that had been prelabeled with [3H] arachidonic acid. In subsequent experiments with unlabeled cells the eicosanoids were quantified by radioimmunoassay.