Evered M D
Prog Neuropsychopharmacol Biol Psychiatry. 1983;7(4-6):469-76. doi: 10.1016/0278-5846(83)90013-1.
A number of neuropeptides have been found to affect fluid intake when injected directly into the brain of various vertebrate species. These include: angiotensin II and its peptide precursors; the tachykinins Substance P, eledoisin and physalaemin; the opioid peptides met- and leu-enkephalin and beta-endorphin; bombesin; neurotensin; and vasopressin. Some of these stimulate drinking, some inhibit water intake, and the tachykinins have opposite effects on thirst depending on the species tested. Very little is known about the site or mechamism of action of most of these peptides or if their effects on thirst are physiological. The exception is angiotensin II, a peptide hormone that is synthesized in the blood in response to hypovalaemia or hypotension and is involved in many aspects of the regulation of blood volume and pressure. Angiotensin II injected intravenously or intracranially stimulates drinking in all reptiles, birds and mammals tested. In addition to its role as a hormone, angiotensin II may also function as a neurotransmitter or neuromodulator, since all of the enzymes and precursors necessary for its synthesis have been found in the central nervous system.
人们发现，将多种神经肽直接注射到各类脊椎动物的大脑中时，会影响其液体摄入量。这些神经肽包括：血管紧张素II及其肽前体；速激肽P物质、eledoisin和蛙皮素；阿片肽甲硫氨酸脑啡肽、亮氨酸脑啡肽和β-内啡肽；蛙皮素；神经降压素；以及血管加压素。其中一些刺激饮水，一些抑制水的摄入，并且速激肽对口渴的影响因所测试的物种而异。对于这些肽中大多数的作用部位或作用机制，或者它们对口渴的影响是否具有生理学意义，人们了解得很少。血管紧张素II是个例外，它是一种肽激素，在血液中因血容量过低或血压过低而合成，参与血容量和血压调节的许多方面。静脉内或颅内注射血管紧张素II会刺激所有经测试的爬行动物、鸟类和哺乳动物饮水。除了作为一种激素的作用外，血管紧张素II也可能作为一种神经递质或神经调节剂发挥作用，因为在中枢神经系统中已发现其合成所需的所有酶和前体。
