Asthma is a chronic disease characterized by acute exacerbation of coughing, dyspnoea, wheezing, and chest tightness. Cell culture model discusses CULTEX technique. Studies on cytotoxicity of air contaminants such as gaseous or particulate compounds and complex mixtures have traditionally used animal experiments because of the difficulties in exposing new cell cultures directly to these substances. In vitro models are discussed. In isolated guinea pig lungs method, drugs are tested for their capability of inhibiting bronchospasm induced by histamine or calcium ionophore. In isolated perfused lung, the simultaneous registration of pulmonary vascular and airway responses to various drugs can be studied. In isolated guinea pig trachea, the effect of histamine, calcium ionophores, bradykinin, leukotrienes, and potassium channel openers are studied. Vascular and airway responses to the isolated lung are discussed. In vivo models are described. Bronchospasmolytic activity in anesthetized guinea pigs is discussed. Thromboxane and prostacyclin are the products of arachidonic acid metabolism. Antihistamines are useful in various anaphylactic manifestations, such as bronchial asthma and serum sickness. Respiratory parameters such as respiratory frequency and respiratory amplitude can be measured in guinea pigs by plethysmograph. Pneumotachograph allows simultaneous measurements of several respiratory and circulatory parameters in anesthetized guinea pigs. Microshock in rabbits are discussed. Inhalation of histamine or other spasmogens can induce symptoms such as asphyctic convulsions resembling bronchial asthma in guinea pigs. The challenging agents are applied as aerosols produced by an ultra sound nebulizer. Airway microvascular leakage in guinea pigs is discussed. As a large number of corresponding immunological reagents are available, the role of cytokines and chemokines in allergic inflammation can also be studied in a rat model.