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目的和方法：本实验通过切除大鼠肾上腺改变垂体的功能状态，利用垂体组织块离体灌流并施加电场刺激的方法，观察垂体前叶内神经纤维对促肾上腺皮质激素（ＡＣＴＨ）释放的影响。结果：参数为强度３０ｍＡ、波宽０．５ｍｓ、频率１０Ｈｚ的电场刺激可明显抑制肾上腺切除９６ｈ后垂体前叶组织块释放ＡＣＴＨ，此效应可被预先给予的河豚毒素（ＴＴＸ）所取消精氨酸加压素（ＡＶＰ）可显著刺激垂体组织块释放ＡＣＴＨ，同样参数的电场刺激对ＡＣＴＨ的分泌无明显抑制作用。γ氨基丁酸（ＧＡＢＡ）Ａ受体拮抗剂Ｂｉｃｕｃｕｌｉｎｅ强烈刺激垂体前叶组织块释放ＡＣＴＨ，电场刺激对其兴奋效应无影响。降钙素基因相关肽（ＣＧＲＰ）受体拮抗剂ＣＧＲＰ８－３７明显抑制垂体前叶组织块ＡＣＴＨ的基础分泌。电场刺激则可使ＡＣＴＨ水平明显提高，此作用可被预先给予的ＴＴＸ完全阻断。Ｂｉｃｕｃｕｌｉｎｅ、ＣＧＲＰ８－３７、ＴＴＸ作用４０ｍｉｎ对分散培养的垂体前叶细胞ＡＣＴＨ分泌无明显影响，对ＡＣＴＨ的前体基因前阿黑皮素原（ＰＯＭＣ）基因表达亦无明显作用。结论：①肾上腺切除９６ｈ后垂体前叶内的神经纤维对ＡＣＴＨ分泌发挥抑制性影响；②ＡＶＰ对垂体组织块ＡＣＴＨ释放的刺激作用强于电场刺?
PURPOSE AND METHODS: In this study, the adrenal gland was excised to change the functional status of pituitary gland. The peri-pituitary tissue was perfused with electric stimulation to observe the effect of nerve fibers on the release of adrenocorticotropic hormone (ACTH) in the anterior pituitary gland. Results: The parameters of 30mA, wave width 0.5ms, frequency 10Hz electric field stimulation can significantly inhibit the release of ACTH 96h after adrenalectomy in the anterior pituitary tissue block, this effect can be pre-given tetrodotoxin (TTX) to cancel the arginine Vasopressin (AVP) can significantly stimulate the release of ACTH pituitary blocks, the same parameters of the electric field stimulation of ACTH secretion was not significantly inhibited. Aminobutyric acid (GABA) A receptor antagonist Bicuculine strongly stimulated the anterior pituitary block release of ACTH, the electric field stimulation has no effect on its excitability. Calcitonin gene-related peptide (CGRP) receptor antagonist CGRP8-37 significantly inhibited the basal secretion of ACTH in the anterior pituitary block. Electric field stimulation can significantly raise the level of ACTH, this effect can be completely blocked by pre-given TTX. The effect of Bicuculine, CGRP8-37 and TTX for 40 min had no significant effect on the ACTH secretion of dispersed anterior pituitary cells, nor did it have any significant effect on the expression of pro-melanocortin (POMC) gene of ACTH. CONCLUSION: ①The nerve fibers in the anterior pituitary gland play an inhibitory role on the secretion of ACTH after adrenalectomy 96h; ② The stimulating effect of AVP on ACTH release in pituitary tissue is stronger than that of electric field.