Gamma-aminobutyric acid (GABA) is the brains major inhibitory neurotransmitter. Studies have shown it is responsible for both the rise of growth hormone (when at rest) or the inhibition of growth hormone (when exercising).33-35 Oral GABA supplementation has increased growth hormone levels in humans. In one study, a single oral dose of 5 grams of gamma aminobutyric acid administered to 19 subjects significantly elevated plasma growth hormone levels compared to placebo-treated controls.36
33. Coiro V, Volpi R, Maffei ML, Caiazza A, Caffarri G, Capretti L, Colla R, Chiodera P. Opioid modulation of the gamma-aminobutyric acid-controlled inhibition of exercise-stimulated growth hormone and prolactin secretion in normal men. Eur J Endocrinol. 1994;131(1):50-5.
34. Rigamonti AE, Muller EE. Gamma-hydroxybutyric acid and growth hormone secretion studies in rats and dogs. Alcohol. 2000;20(3):293-304.
35. Vescovi PP, Volpi R, Coiro V. Alcoholism abolishes the gamma-aminobutyric acid (GABA)ergic control of GH secretion in humans. Alcohol. 1998;16(4):325-8.
This looks like a neat enough aspect of GABA supplementation in and of itself, the whole "ability to raise your GH secretion" thing that is, but I can't find a ton of studies demonstrating efficacy as a sleep aid.
SUSTAINED DRUG-INDUCED ELEVATION OF BRAIN GABA IN THE RAT†
T. L. Perry, Shirley Hansen
Abstract— The contents of GABA, homocarnosine, and β-alanine can be raised in rat brain for long periods of time by the continued administration of phenelzine, aminooxyacetic acid (AOAA), or isonicotinic acid hydrazide (INH). These 3 compounds apparently act by preferential inhibition of the enzyme GABA aminotransferase (GABA-T). Oral administration of phenelzine (20 mg/kg per day) caused a 25–50 per cent increase in GABA levels in rat brain, but produced appreciable toxic side effects. A similar increase in GABA levels in brain resulted from oral administration to rats of INH in a dosage of 60 mg/kg per day, without production of any obvious toxic effects. Simultaneous administration of large doses of pyridoxine did not abolish the GABA-elevating effect of INH. Brain GABA levels in the rat were increased by approx. 50 per cent by daily injections of AOAA (2.5 mg/kg per day). At this low dosage, AOAA injections in rats could be continued for at least 6 weeks without producing evident toxic effects.
Oral administration of large amounts of GABA, on the other hand, failed to increase the content of GABA in the brains of rats not treated with GABA-T inhibitors, and failed to produce any further increase of brain GABA levels in rats treated with AOAA..
The Interaction Between GABA and Dopamine: Implications for Schizophrenia
James C. Garbutt and Daniel P. van Kammen
"...Although it was originally thought that GABA might be useful in treating schizophrenia because of its inhibition of dopaminergic activity, recent data have shown that in certain models GABA has the opposite effect on dopaminergic functions. Regardless of the relationship of GABA to dopamine, neither biochemical nor pharmacological studies have been able to demonstrate a clear and reproducible GABA disturbance in schizophrenia..."
How does the first study on GH and the following study correlate?
GHRH and sleep.
Obal F Jr, Krueger JM.
Source
Department of Physiology, A. Szent-Györgyi Medical Center, University of Szeged, 6720, Szeged, Hungary.
[email protected]
Abstract
Suppression of endogenous GHRH (competitive antagonist, antibodies, somatostatinergic stimulation, high doses of GH or insulin-like growth factor) results in sA significant portion of the total daily growth hormone (GH) secretion is associated with deep non-REM sleep (NREMS). GH secretion is stimulated by the hypothalamic neurohormone, GH-releasing hormone (GHRH). Exogenous GHRH promotes NREMS in various species. imultaneous inhibition of NREMS. Mutant and transgenic animals with a defect in GHRHergic activity display permanently reduced NREMS which cannot be reversed by means of GH supplementation. GHRH contents and mRNA levels in the hypothalamus correlate with sleep-wake activity during the diurnal cycle and sleep deprivation and recovery sleep. Stimulation of NREMS by GHRH is a hypothalamic action. GABAergic neurons in the anterior hypothalamus/preoptic region are candidates for mediating promotion of NREMS by GHRH. In contrast to NREMS, stimulation of REMS by GHRH is mediated by GH. Simultaneous stimulation of NREMS and GH secretion by GHRH may promote adjustment of tissue anabolism to sleep.
PMID: 15336237 [PubMed - indexed for MEDLINE]
BTW, I keep seeing sources citing dosages of 200 MG three times daily; is taking such an excessive dosage, daily possibly, wise? Can you possibly, since your resting using this supplement, increase your GH uncomfortably high? (I'm ignorant)
GH stimulates the production of another chemical called insulin-like growth factor-1 (IGF-1) by the liver and by many body tissues.
(COPY AND PASTE)
HGH Increases Inflammation
Human growth hormone consists of several distinct -- but similar -- chemicals. Scientists refer to these distinct substances by their molecular weight. Each type of growth hormone appears to have unique properties, according to a June 2010 report in the "International Journal of Pediatric Endocrinology." The 22 kilodalton chemical often causes side effects such as swelling. An investigation published in the 2004 volume of the "Journal of Clinical Endocrinology and Metabolism" determined whether the 20 kilodalton chemical produced adverse events as well. Patients with growth-hormone deficiency received daily injections of HGH for four months. This treatment increased IGF-1 and insulin. It also increased lean body mass. Many patients, however, experienced swelling in their arms and legs.
HGH Causes Joint Pain
People infected with the human immunodeficiency virus have difficulty maintaining their weight. Moreover, medications treating HIV often cause increases in body fat. Growth hormone can help resolve these issues, according to a July 2007 report in the "Scandinavian Journal of Infectious Diseases." Yet, the benefits of HGH may come at a cost. A paper in the November 2007 issue of "Clinical Therapeutics" reviewed studies testing the effectiveness of growth hormone in HIV patients. At least 30 percent of the participants in these reports experienced either muscle or joint pain during hormone therapy. Many patients also experienced diabetic symptoms such as elevations in blood sugar.
IGF-1 Elevates Blood Sugar
Insulin-like growth factor 1 also affects body composition. An anabolic hormone, IGF-1 stimulates muscle growth in laboratory animals. A July 2011 article in "Endocrinology" showed that injecting mice with IGF-1 increased their body size and muscle mass. The authors observed no evidence of IGF-1 toxicity in this report, but other studies have shown that the hormone causes unwanted side effects. A clinical trial offered in the 2007 volume of the "Journal of Clinical Endocrinology and Metabolism" tested the effects of replacement therapy with IGF-1 in children. Participants received twice daily doses of the hormone for several years. About half the kids experienced brief episodes of hypoglycemia. This elevation in blood sugar caused seizures in a few cases.
IGF-1 Causes Headaches
Unusually small children often develop health problems as adults. Genetic defects in the IGF-1 system might underlie short stature, according to a July 2011 report in "Hormone Research in Pediatrics." This finding suggests that IGF-1 might prove useful in increasing height. A study presented in the 2010 volume of the "Journal of Clinical Endocrinology and Metabolism" tested this hypothesis in children with low levels of IGF-1. Twice daily injections for a year significantly increased the patients' height. This treatment, however, also caused headaches in nearly 40 percent of the kids. Nearly 25 percent of the children also reported feelings of nausea.
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http://www.livestrong.com/article/517690-side-effects-of-hgh-igf-1/#ixzz1wNDURDw2)