Human growth hormone (GH) is a 22kD monomeric protein produced and stored in somatotrophs in the anterior pituitary gland. GH is released from the pituitary into the bloodstream in a pulsatile manner under the regulatory control of hypothalamic somatostatin (SS) and GH-releasing factor (GHRF). The timing and frequency of GH release appears to be regulated by somatostatin, while the amplitude of GH release is determined by GHRF. A minor fraction (~10%) of GH in circulation exists in a smaller 20kD form. GH has profound effects on tissue growth and metabolism, which is thought to be mediated through GH-dependent production of IGF-I and IGF-II, and their associated binding proteins. GH apparently stimulates IGF production after binding to specific cell surface receptors in the liver and, possibly, other tissues. Almost 50% of GH in circulation is bound to a high affinity GH binding protein (GHBP), which represents the extracellular domain of the GH receptor. Deficient GH secretion can occur in a number of clinical conditions. However, evaluation of GH deficiency is complicated by the episodic nature of GH secretion and low circulating levels. A variety of physiologic and pharmacologic stimuli have been used to stimulate pituitary GH release during testing and failure to achieve a normal serum GH level in response to at least 2 GH stimulation or provocative tests is considered to be a diagnostic of GH deficiency. The definition of a normal serum GH response is controversial, although published values generally range from 5-10ng/ml. GH excess (or acromegaly) can be caused either by direct GH hypersecretion or GH excess secondary to GHRF hypersecretion.
Kit Components:G9000-01A: Microtiter Plate 1x96wellsG9000-01B: Pab (HRP) 1x12mlG9000-01C: Standard (50ng/ml) 1x1 vialG9000-01D: Standard (25ng/ml) 1x1 vialG9000-01E: Standard (12ng/ml) 1x1 vialG9000-01F: Standard (6ng/ml) 1x1 vialG9000-01G: Standard (2ng/ml) 1x1 vialG9000-01H: Standard (0ng/ml) 1x1 vialG9000-01J: Sample Diluent 1x7mlG9000-01K: Substrate A 1x10mlG9000-01L: Substrate B 1x10mlG9000-01M: Stop Solution 1x14mlG9000-01N: Wash Buffer (20 X) 1x60ml
Sensitivity:~0.5ng/ml
Storage and Stability:Store at 4°C. Stable for at least 6 months. For maximum recovery of product, centrifuge the original vial prior to removing the cap.
