In fact, when the siRNA that inhibits HIF-1 expression was administered to experimental animals with allergic diseases, the progress of the disease was controlled.[14,15] In our former studies, we also found that Hif-1 and VEGF levels decreased after the treatment of experimental animals with allergic asthma, with benzaldehyde.[16] However, in this experiment, the expression of these genes remained increased because of the potential hypoxic effect of hypergravity. The gene discussed is HIF1A; the disease is allergic asthma.