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1、第三节第三节 肾脏泌尿功能的调节肾脏泌尿功能的调节 Regulation of urine formation of the kidney尿生成的调节尿生成的调节 regulation of urine formation 肾血流量的调节肾血流量的调节神经神经体液调节体液调节 regulation of renal blood flow nervous and humonal control (对滤过的调节对滤过的调节)(对重吸收和分泌对重吸收和分泌)自身自身 神经神经 体液体液调节调节 调节调节 调节调节 ADH 醛固酮醛固酮 甲状旁腺素甲状旁腺素 Aldosterone parathyro
2、id hormone 一、抗利尿激素一、抗利尿激素 antidiuretic hormone,ADH n合成部位:视上核合成部位:视上核(supraoptic nucleus)、室旁核、室旁核(paraventricular nucleus)合成合成ADHn运输:运输:丘脑丘脑垂体束垂体束n贮存释放:神经垂体(贮存于膨大神经末梢中)贮存释放:神经垂体(贮存于膨大神经末梢中)n 前激素前激素 ADH 九肽九肽 蛋白水解酶蛋白水解酶n靶器官:远曲小管集合管靶器官:远曲小管集合管 The hypothalamus contains two types of neurons that synthesi
3、ze ADH in the supraoptic nucleus and paraventricular nucleus.once ADH is synthesized,it is transported down the axons of the neurons to their tips,terminating in the posterior pituitary gland.n作用:作用:1.提高远曲小管和集合管上皮细胞对水的通透提高远曲小管和集合管上皮细胞对水的通透性,促进水的重吸收尿液浓缩、尿量减少性,促进水的重吸收尿液浓缩、尿量减少(抗利尿)(抗利尿)主要作用主要作用。The mo
4、st important renal action of ADH is to increase the water permeability of the distal tubule,collecting tubule.This effect helps the body to conserve water in circumstances such as dehydration.2.增加内髓部集合管对尿素的通透性并减少肾增加内髓部集合管对尿素的通透性并减少肾髓质的血流量。髓质的血流量。ADH increases the urea permeability of collecting tubu
5、le in inner zone and decreases the blood flow in medulla.3.促进髓绊升支粗段对促进髓绊升支粗段对NaCl的重吸收,使直小的重吸收,使直小血管收缩。血管收缩。ADH increases the reabsorption of NaCl in thick segment of ascending limb and so leads to constriction of vasa recta.(一)、作用机理:(一)、作用机理:ADH与远曲小管、集合管上皮细胞管周膜上受体结合与远曲小管、集合管上皮细胞管周膜上受体结合 激活膜内的腺苷酸环化酶激
6、活膜内的腺苷酸环化酶 上皮细胞中上皮细胞中cAMP 管腔膜管腔膜中蛋白激酶激活中蛋白激酶激活 膜蛋白磷酸化膜蛋白磷酸化 膜构型改变膜构型改变 水通水通道开放管腔膜对水通透性道开放管腔膜对水通透性 。ADH ,水通道小泡内移,水通道小泡内移,对水通透性对水通透性 。ADH combines with the receptor in basolateral membrane and activated the adenylate cyclase,it produces cyclic adenosine monophosphate,which leads to activation of prote
7、in kinase in basolateral membrane,then the membrane protein is phosphorylated,so the configuration of membrane changes,this process increases the permeability to water by the open of water channel.(二)(二)ADH分泌的调节分泌的调节(the regulation of ADH secretion)血 浆 晶 体 渗 透 压 的 改 变血 浆 晶 体 渗 透 压 的 改 变 (the change
8、of crystal osmotic pressure)有效刺激因素有效刺激因素effective stimuli 循环血量的改变循环血量的改变 (the change of effective blood volume)1、血浆晶体渗透压的改变、血浆晶体渗透压的改变特点:敏感,晶体渗透压改变特点:敏感,晶体渗透压改变 12%时即有反应。时即有反应。电解质电解质(+)有效有效 尿素尿素 无效无效感受器:位于视上核及其附近区域。感受器:位于视上核及其附近区域。大量出汗、腹泻、失水大量出汗、腹泻、失水 血浆晶体渗透压血浆晶体渗透压 视上核视上核及其周围区域渗透压感受器及其周围区域渗透压感受器(+)
9、神经垂体神经垂体 膨大神经膨大神经末梢去极化末梢去极化 释放释放ADH 远曲小管、集合管对水通远曲小管、集合管对水通透性透性 对水重吸收对水重吸收 ,尿液浓缩,尿液浓缩 尿量减少。尿量减少。The precise way that the osmotic concentration of the extracellular fluids controls ADH secretion is not clear.Yet somewhere in or near the hypothalamus are modified neuron receptors called osmoreceptors.w
10、hen the extracellular fluid becomes too concentrated,fluid is pulled by osmosis out of the osmoreceptor cell,initiating appropriate nerve signals in the hypothalamus to cause additional ADH secretion.水利尿水利尿water diuresis 大量饮清水大量饮清水 尿量尿量 饮饮1000ml清水,隔清水,隔30分钟分钟 尿量尿量 ,(,(1小时末达高峰,小时末达高峰,23小时恢复)小时恢复)饮饮10
11、00ml NS,隔,隔30分钟分钟 变化不大变化不大 2、循环血量的改变(容量感受器途径)、循环血量的改变(容量感受器途径)过度输液,血量过多(+)左心房内膜下容量感受器 迷走N,传入冲动 中枢,间接抑制下丘脑垂体后叶系统 释放ADH 远曲小管集合管对水通透性 对水重吸收 尿量 。When blood volume increases because of excess transfuse,the volume receptor in endometrium of left atrium sends impulse through Vagus nerve to center and inhib
12、it the release of ADH by Hypothalami-Pituitary posterior lobe system,so the water permeability in distal tubule and collecting tubule decreases,therefore the reaborption of water decreases and the urine volume increases.3、其它因素、其它因素 AP (+)颈动脉窦压力感受器颈动脉窦压力感受器 窦窦N ADH反射性释放反射性释放 尿量尿量痛刺激、情绪紧张痛刺激、情绪紧张 ADH
13、尿量尿量 弱冷刺激弱冷刺激 ADH 尿量尿量下丘脑病变累及视上核、室旁核下丘脑病变累及视上核、室旁核 ADH合成合成释放障碍释放障碍 尿崩症尿崩症(diabetes insipidus)。When arterial pressure increases,pressorecepto in carotid sinus sends signals to hypothalamic nuclei through sinus nerve that decreases ADH secretion.ADH secretion can also be controlled by other stimuli su
14、ch as pain and nervous mood.二、醛固酮的作用(二、醛固酮的作用(Aldosterone)分泌部位:肾上腺皮质球状带分泌部位:肾上腺皮质球状带靶器官:远曲小管集合管靶器官:远曲小管集合管作用:促进对作用:促进对Na+的主动重吸收,同时促进的主动重吸收,同时促进 K+的排出的排出保保Na+排排K+作用。作用。Aldosterone,secreted by the zona glomerulose cells of the adrenal cortex,is an important regulator of sodium reabsorption and potassi
15、um secretion by the renal tubules.The primary site of aldosterone action is on the principal cells of the cortical collecting tubule.the mechanism by which aldosterone increase sodium reabsorption while at the same time increasing potassium secretion is stimulating the sodium-potassium ATPase pump o
16、n the basolateral side of the cortical collecting tubule membrane.(一)作用机制:(一)作用机制:醛固酮进入远曲小管集合管的上皮细胞后醛固酮进入远曲小管集合管的上皮细胞后 与胞浆受体结合与胞浆受体结合形成激素形成激素胞浆受体复合物胞浆受体复合物 通过核膜通过核膜 与核中受体结合与核中受体结合 激素激素核受体复合物核受体复合物 促进促进mRNA的合成的合成 醛固酮醛固酮促进小管上皮细胞促进小管上皮细胞Na+泵运转泵运转诱导蛋白诱导蛋白 促进生化氧化提供促进生化氧化提供ATP 促进加强促进加强Na+增加管腔膜对增加管腔膜对Na+通透性通透性的主动重吸收的主动重吸收(保保Na+)造成小管腔内负电位造成小管腔内负电位 K+被分泌到被分泌到小管液(排小管液(排K+)Aldosterone diffuses readily to the interior of the tubulaar epithelial cells and combines with a highly specific cytoplasmic receptor