疼痛对垂体中叶超微结构的影响

EFFECT OF PAIN ON ULTRASTRUCTURE OF INTERMEDIATE LOBE OF PITUITARY(ABSTRACT)

β-内啡肽(β-endorphin)是主要由垂体产生的吗啡样物质,具有镇痛、催眠、欣快及影响行为等作用。近来应用放射受体分析法^([1,2]),发现电针后,大鼠垂体吗啡样物质减少;电击鼠足^([3]),血浆内β-内啡肽浓度上升5~6倍,并导致止痛;在慢性疼痛及妇女分娩时,垂体内啡肽大量排出^([4]);针刺可促使内啡肽的释放,并可达到镇痛^([5~7])。

Pain just tolerable was caused intermittently by electric stimulation on rat’s tail or by distented baloon in stomach for 30 min.The changes of intermediate lobe are summarized as follows:(1)The cell body,nucleus or nucleolus was hypertrophied.The number of rough endoplasmic reticulum,particularly of its vesicular cisternae was increased.Golgi complex enlarged.The ribosome multiplied.All of these change indicated that the activity of cells was increased and the rate of synthesis enhanced.(2)Both the secretory granules shifted to the periphery of cell body and some of them showed pale density.These changes were interpreted as increase of seretory activity.(3)The mitochondria became enlarged and the crsitae in them were changed into tubular form.This suggested an acceleration of cell metabolism,which might provide a large amount of energy.(4)There was no degenerative change.(5)The cytological changes caused by visceral pain were simillar with,but more striking than,those caused by somatic pain.(6)The secretions were increased,among which β-endorphin and ACTH etc were known to be closely related to analgesia.