Brain serotonin content: physiological dependence on plasma tryptophan levels.
نویسندگان
چکیده
Brain serotonin cocentrations at 1 p.m. were significantly elevated 1 hour after rats received a dose of L-tryptophan (12.5 milligrams per kilogram. intraperitoneally) smaller than one-twentieth of the normal daily dietary intake. Plasma and brain tryptophan levels were elevated 10 to 60 minutes after the injection, but they never exceeded the concentrationis that occur nocturnally in untreated aninmals as result of their normal 24-hour rhythms. These data suggest that physiological changes in plasma tryptophan concentration influenice brain serotonin levels.
منابع مشابه
Effect of chronic corn consumption on serotonin content of rat brain.
SEROTONIN, a putative neurotransmitter in the mammalian central nervous system, is synthesized in the brain by the 5-hydroxylation and decarboxylation of the essential aminoacid L-tryptophan1 ' 2. The control of serotonin biosynthesis seems to involve a different mechanism from that responsible for catecholamine biosynthesis3' 4 in its dependence on the availability of the amino-acid precursor'...
متن کاملBrain serotonin content: physiological regulation by plasma neutral amino acids.
When plasma tryptophan is elevated by the injection of tryptophan or insulin, or by the consumption of carbohydrates, brain tryptophan and serotonin also rise; however, when even larger elevations of plasma tryptophan are produced by the ingestion of protein-containing diets, brain tryptophan and serotonin do not change. The main determinant of brain tryptophan and serotonin concentrations does...
متن کاملLow tryptophan diet increases stress-sensitivity, but does not affect habituation in rats.
Cerebral dysfunction of 5-HT (serotonin) has been associated with stress response and with affective disorders. Stress alone is insufficient to induce depression, since only a minor proportion of subjects that have experienced stressful life events develop depressive episodes. We investigated whether long-term brain 5-HT depletion induced in rats by a diet with low content of its precursor tryp...
متن کاملDose-dependent effects of tryptophan on learning and memory.
The concentration of 5-hydroxytryptamine (5-HT, Serotonin) varies as a result of physiological changes in the availability of its precursor tryptophan to the serotonergic neurons in the brain. Increase in brain tryptophan occurs following an increase in plasma tryptophan concentration. Tryptophan intake increases brain serotonin metabolism and enhances memory. The Present study was designed to ...
متن کاملThe effect of tryptophan depletion on brain activation measured by functional magnetic resonance imaging during the Stroop test in healthy subjects.
We investigated the role of serotonin in cognitive activation of the frontal cortex. The serotonergic system was affected by the administration of an amino acids mixture without tryptophan (tryptophan depletion). In a placebo-controlled double-blind cross-over study with 20 healthy volunteers, we tested the hypothesis that a tryptophan (serotonin) decrease affects the activation of prefrontal c...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Science
دوره 173 3992 شماره
صفحات -
تاریخ انتشار 1971