In vivo effect of volume expansion on rectal gland function. II. Hemodynamic changes.
In vivo effect of volume expansion on rectal gland function. II. Hemodynamic changes.
复制标题
体内体积扩张对直肠腺功能的影响。
DOI：
10.1152/ajpregu.1984.246.1.r67
复制
发表时间：
1984
期刊：
影响因子：
--
通讯作者：
Epstein,FH
中科院分区：
文献类型：
--
作者：
Solomon,RJ;Taylor,M;Rosa,R;Silva,P;Epstein,FH
血管内容积扩张导致棘角鲨体内直肠腺的液体分泌和血流速度增加300%。类似的增加也观察到通过导管从背主动脉的体积膨胀角鲨的直肠腺灌注。通过体积扩张刺激直肠腺分泌与直肠腺分泌的氯与消耗的氧的比率和氧提取率的变化无关，这表明血流量的增加是支持氯分泌速率增加所必需的。用布美他尼（10（-4）M）灌注切除的腺体完全抑制了对体积扩张的分泌反应，但不能阻止血流量的增加。布美他尼还抑制二丁酰腺苷3 '，5'-环一磷酸和茶碱诱导的氯化物分泌增加，但不抑制充血反应。生长抑素抑制前列腺对体积扩张的分泌反应，但不阻止血流量的增加。虽然血流量的增加是必要的，以支持增加的能量需求，增强运输，分泌反应和血流量的增加似乎是独立的调节和介导的，至少部分，由体液因素。
Intravascular volume expansion causes a 300% increase in the rate of fluid secretion from, and blood flow to, the in vivo rectal gland of the spiny dogfish Squalus acanthias. Similar increases are also observed in explanted rectal glands perfused through a catheter from the dorsal aorta of a volume-expanded dogfish. Stimulation of rectal gland secretion by volume expansion is not associated with a change in the ratio of chloride secreted to oxygen consumed by the rectal gland and the oxygen extraction ratio, suggesting that an increase in blood flow is necessary to support the increased rate of chloride secretion. Perfusion of the explanted gland with bumetanide (10(-4) M) completely inhibits the secretory response to volume expansion but does not prevent the increase in blood flow. Bumetanide also inhibits dibutyryl adenosine 3',5'-cyclic monophosphate- and theophylline-induced increases in chloride secretion but does not inhibit the hyperemic response. Somatostatin inhibits the secretory response of the explanted gland to volume expansion but does not prevent the increase in blood flow. Although an increase in blood flow is necessary to support the increased energy requirement of enhanced transport, the secretory response and the increase in blood flow appear to be independently regulated and mediated, at least in part, by humoral factors.