How does allergy manifest in rats? - briefly
Allergic responses in rats are characterized by nasal discharge, sneezing, pruritus, dermal swelling, and often impaired respiration or lethargy. Histological examination usually shows eosinophil infiltration and increased serum IgE concentrations.
How does allergy manifest in rats? - in detail
Allergic responses in laboratory rats present a combination of observable clinical signs, measurable immunological parameters, and physiological alterations. Cutaneous manifestations include erythema, edema, and pruritus, often localized to the site of antigen exposure but capable of spreading systemically. Respiratory involvement may appear as nasal discharge, sneezing, bronchoconstriction, and increased airway resistance, detectable through plethysmography or spirometric assessment. Gastrointestinal symptoms comprise reduced food intake, diarrhea, and weight loss, reflecting mucosal inflammation.
Immunological indicators provide objective confirmation of hypersensitivity. Elevated serum IgE concentrations, detected by enzyme‑linked immunosorbent assay, correlate with the intensity of the reaction. Mast cell degranulation, identified through histological staining for tryptase, releases histamine, prostaglandins, and leukotrienes, which drive the observed tissue swelling and bronchial tone changes. Cytokine profiling typically reveals increased levels of interleukin‑4, interleukin‑5, and interleukin‑13, reflecting a Th2‑biased response.
Behavioral changes often accompany the physiological disturbances. Rats may exhibit increased grooming, restlessness, or decreased locomotor activity, which can be quantified using video‑tracking systems. Pain‑related behaviors, such as vocalization or abdominal guarding, may arise when the allergic reaction involves deep tissue inflammation.
Laboratory monitoring can include:
- Serial measurement of serum IgE and allergen‑specific IgG subclasses.
- Flow cytometric analysis of peripheral blood eosinophils and basophils.
- Histopathological examination of skin, lung, and intestinal tissues for inflammatory infiltrates.
- Pulmonary function testing to assess airway hyper‑responsiveness.
These combined observations allow researchers to characterize the full spectrum of allergic pathology in rats, facilitating the evaluation of therapeutic interventions and the extrapolation of findings to human allergic diseases.