Bealer S L, Schneider E G
Am J Physiol. 1985 Feb;248(2 Pt 2):R161-5. doi: 10.1152/ajpregu.1985.248.2.R161.
The effects of extracellular fluid volume depletion on plasma corticosterone concentration (Pcort) and plasma volume in rats were determined after recovery from either electrolytic ablation of the periventricular tissue surrounding the anteroventral third ventricle (AV3V region) or control surgery. Rats received either furosemide injections and sodium-free chow or isotonic saline injections and continued access to sodium-replete food. One week after these injections some animals were decapitated and trunk blood collected for analysis of Pcort by radioimmunoassay. The remainder of the rats were implanted with femoral arterial catheters to obtain blood samples for measurement of plasma and blood volumes by calculating dilution of 125I-labeled serum albumin. Volume-replete rats with AV3V lesions had significantly higher Pcort concentrations and smaller plasma and blood volumes than volume-replete control-operated animals. Furthermore, volume depletion induced by furosemide caused a significant increase in Pcort concentration only in rats with AV3V ablations, whereas plasma and blood volumes were significantly lowered in both groups. These data demonstrate that AV3V periventricular ablation results in a chronic elevation of Pcort in the volume-replete animals and an exaggerated glucocorticoid response to volume depletion. These data show that decreased PV characteristic of animals with AV3V lesions is not due to glucocorticoid insufficiency.
在从前脑室前腹侧第三脑室（AV3V区域）周围的室周组织电解消融或对照手术恢复后，测定细胞外液容量耗竭对大鼠血浆皮质酮浓度（Pcort）和血浆容量的影响。大鼠接受速尿注射和无钠食物，或等渗盐水注射并继续给予富含钠的食物。这些注射一周后，一些动物被断头，收集躯干血，通过放射免疫测定法分析Pcort。其余大鼠植入股动脉导管，通过计算125I标记血清白蛋白的稀释度来获取血样，以测量血浆和血容量。与容量充足的对照手术动物相比，患有AV3V损伤的容量充足的大鼠具有显著更高的Pcort浓度以及更小的血浆和血容量。此外，速尿引起的容量耗竭仅在患有AV3V消融的大鼠中导致Pcort浓度显著升高，而两组的血浆和血容量均显著降低。这些数据表明，AV3V室周消融导致容量充足的动物中Pcort长期升高，以及对容量耗竭的糖皮质激素反应过度。这些数据表明，患有AV3V损伤的动物的血浆容量降低并非由于糖皮质激素不足。
