ABSTRACT
<p><b>OBJECTIVE</b>To investigate the distribution and expression of corticotropin releasing factor (CRF) in spinal cord, hypothalamus and third ventricle of cerebrum, of the hypersensitive viscera rats, and to research on the mechanism of CRF in the hypersensitive vicera signal conduction pathway in IBS (irritable bowel syndrome) and to investigate possible active mechanisms of tongxie prescription on IBS.</p><p><b>METHOD</b>Forty SD rats were divided randomly into three groups. The rats of model No. 1 were sensitized by injecting egg albumin into abdominal cavity. The rats of model No. 2 were sensitised by conditional stimulus and unconditional stimulus. The two model groups were both divided randomly into two groups. The five groups were given intragastric administration with Tongxie prescription or normal saline for four weeks. Then quantitative analysis of CRF in the lumbosacral spinal cord and brain of rats were achieved by immunohistochemical method and computerized image system.</p><p><b>RESULT</b>The sensitivity of the groups being treated with tongxie prescription were much lower than the model groups (P < 0.01). The immunohistochemical method showed that CRF was expressed in the lumbar intumescentia of spinal cord, hypothalamus and the diaphragmatic surface of third ventricle of cerebrum. The CRF positive index of the model groups was higher than that of the blank group (P < 0.01). The CRF positive index of the healing groups was lower than that of the model groups (P < 0.01). The CRF positive index of the healing groups was higher than that of the blank group (P < 0.01).</p><p><b>CONCLUSION</b>The two model rats evoked by two different stimulation both appeared visceral hypersensitivity state. CRF is related to stress. The increase of CRF expression in the lumbar intumescentia of spinal cord, hypothalamus and the diaphragmatic surface of third ventricle of cerebrum showed that CRF is critical to the introduce of stimulus signal of vicera. Tongxie prescription can significantly decrease CRF expression. This is one mechanism to decrease sensitivity of hypersensitive viscera rats.</p>