Demonstration of pro-opiomelanocortin mRNA in pituitary adenomas and para-adenomatous gland in cushing's disease and Nelson's syndrome

Pro-opiomelanocortin (POMC) mRNA was demonstrated in pituitary adenomas from 16 patients with Cushing's disease and 10 with Nelson's syndrome. The intensity of signal was significantly greater in Nelson's syndrome than in Cushing's disease and there was a trend towards a greater proportion of positive cells. This probably reflects inhibition of POMC gene expression by the high circulating levels of cortisol in Cushing's disease. In the para-adenomatous gland, the intensity of signal was variable in cells showing Crooke's hyaline change, ranging from negative to strongly positive, in keeping with the functional heterogeneity of corticotrophs. In one case, junctional corticotrophs were present and these were more intensely stained than anterior lobe corticotrophs in the same gland. This supports the concept that these cells are subject to different regulatory influences from corticotrophs in the anterior lobe. Whether this is related to differences in embryological origins or to local factors is at present unclear.     

含P物质的红核神经元至脊髓的投射——HRP逆行追踪和免疫组化结合法研究

用辣根过氧化物酶(HRP)逆行标记与免疫细胞化学相结合方法,在大鼠红核内观察到HRP阳性与P物质反应阳性的双重标记神经元。双标细胞以对侧为主,同侧较少。首次证实了红核脊髓束中有部分纤维是SP能的,并可投射至颈、胸、腰段脊髓。