EA 3453 Systèmes Neuromodulateurs des Comportements Ingestifs, Université Henri Poincaré, Nancy, France; Laboratoire de Physiologie, Faculté de Médecine, Université des Sciences de la Santé, Libreville, Gabon.
EA 3453 Systèmes Neuromodulateurs des Comportements Ingestifs, Université Henri Poincaré, Nancy, France.
Physiol Behav. 2021 Mar 1;230:113308. doi: 10.1016/j.physbeh.2020.113308. Epub 2020 Dec 30.
We investigated the effect of central administration of angiotensin II (AngII) on a specific salt appetite (SSA) in homozygous diabetes insipidus Brattleboro (DI) rats because this stimulus induces such a response in all other rat strains. DI rats have a deficiency in the synthesis of arginine vasopressin (AVP) and a reduced content of pituitary oxytocin (OT). They are characterized also by polyuria, polydipsia, and they seldom ingest high concentrations of NaCl solutions. We also tested if the appetite can be influenced by neurohypophyseal hormones especially oxytocin (OT) because it inhibits SSA in other animals. DI rats and Long Evans (LE) controls were fed ad libitum and given a choice between water, and either 0.9% or 1.8% NaCl. The data showed a significant increase of daily spontaneous water intake in DI compared with LE rats. Both DI and LE ingested similar small spontaneous volumes of the isotonic NaCl solution, but DI rats drank significantly less hypertonic NaCl than the LE controls. I.c.v infusion of AngII induced significant sodium intake in LE rats, but only raised water intake in DI rats. When combined with i.c.v. Ang II, OVT enhanced salt intake in LE animals while AVP attenuated water intake in both groups of rats and blocked NaCl intake completely in LE rats. In conclusion, DI rats did not demonstrate a SSA in response to central administration of AngII, although the drinking of water was enhanced. In combination with i.c.v. AngII, AVP inhibits water drinking in both DI and LE rats. In the LE controls OT attenuates AngII-induced SSA but has no effect in DI rats.
我们研究了中枢给予血管紧张素 II（AngII）对同源性糖尿病性尿崩症 Brattleboro（DI）大鼠特定盐食欲（SSA）的影响，因为这种刺激会在所有其他大鼠品系中引起这种反应。DI 大鼠缺乏精氨酸加压素（AVP）的合成和垂体催产素（OT）的含量减少。它们还表现为多尿、多饮，很少摄入高浓度的 NaCl 溶液。我们还测试了神经垂体激素，特别是催产素（OT）是否可以影响食欲，因为它会抑制其他动物的 SSA。DI 大鼠和 Long Evans（LE）对照大鼠自由进食，并在水和 0.9%或 1.8%NaCl 之间进行选择。数据显示，与 LE 大鼠相比，DI 大鼠的每日自发饮水量显著增加。DI 和 LE 大鼠均摄入相似的小体积等渗 NaCl 溶液，但 DI 大鼠摄入的高渗 NaCl 明显少于 LE 对照大鼠。中枢给予 AngII 可诱导 LE 大鼠显著摄入钠，但仅增加 DI 大鼠的饮水量。当与中枢给予 AngII 联合使用时，OT 增强了 LE 动物的盐摄入量，而 AVP 则减弱了两组大鼠的饮水量，并完全阻断了 LE 大鼠的 NaCl 摄入量。总之，尽管 DI 大鼠的饮水量增加，但中枢给予 AngII 并未引起 SSA。与中枢给予 AngII 联合使用时，AVP 抑制 DI 和 LE 大鼠的饮水。在 LE 对照大鼠中，OT 减弱了 AngII 诱导的 SSA，但对 DI 大鼠没有影响。
