What does allergy look like in rats? - briefly
Allergic reactions in rats appear as skin inflammation, respiratory distress, and altered behavior such as excessive scratching or reduced activity. Common signs include reddened or swollen skin, nasal discharge, sneezing, and increased serum IgE concentrations.
What does allergy look like in rats? - in detail
Allergic responses in laboratory rats present with a reproducible set of physiological and behavioral alterations that can be quantified for experimental purposes.
Cutaneous manifestations include erythema, edema, and pruritic papules at sites of antigen exposure. In some strains, dermal lesions progress to exudative dermatitis with crust formation.
Respiratory signs consist of nasal rubbing, sneezing, increased respiratory rate, and audible wheezing. Bronchial hyper‑responsiveness may be demonstrated by reduced airway resistance following methacholine challenge.
Gastrointestinal involvement appears as reduced food intake, loose stools, and occasional vomiting. Weight loss and decreased growth rate are common secondary outcomes.
Systemic indicators comprise elevated body temperature, tachycardia, and lethargy. Behavioral changes such as grooming excess, agitation, or reduced exploratory activity provide additional read‑outs of discomfort.
Immunological markers detectable in blood or tissue samples include:
- Serum IgE specific to the administered allergen
- Increased eosinophil count in peripheral blood and tissue infiltrates
- Up‑regulated Th2 cytokines (IL‑4, IL‑5, IL‑13) in spleen or lymph node extracts
- Histamine surge measurable within minutes of antigen challenge
Typical experimental allergens used to induce these reactions are ovalbumin, house‑dust‑mite extract, and cockroach protein. Sensitization protocols usually involve intraperitoneal or subcutaneous priming followed by aerosol or intranasal challenge to elicit airway inflammation.
Severity grading relies on a combination of clinical scoring (skin, respiratory, gastrointestinal) and quantitative laboratory data (IgE titers, eosinophil percentages). Histopathological examination of lung tissue reveals peribronchial eosinophilic infiltrates, mucus hypersecretion, and epithelial edema, confirming the allergic phenotype.
Overall, allergic reactions in rats are characterized by observable skin lesions, respiratory distress, gastrointestinal upset, systemic signs, and measurable immunological changes, providing a comprehensive platform for studying hypersensitivity mechanisms.