Introduction
Obesity, which is characterized by excessive accumulation of adipose tissue in the body, has become one of the greatest public health challenges. Obesity is not only associated with health problems linked to increased weight-dependent pressure overload on lung, joints and bones, but also a important risk factor for life-threatening diseases such as cardiovascular diseases, type 2 diabetes and certain cancers.
Ghrelin is synthesized as a preprohormone, and then proteolytically processed to yield a 28-amino acid peptide. Synthesis of ghrelin occurs predominantly in epithelial cells lining the fundus of the stomach, with smaller amounts produced in the placenta, kidney, pituitary and hypothalamus.
Ghrelin has emerged as the first circulating hunger hormone. Ghrelin increases food intake and thus fat mass by an action exerted at the level of the hypothalamus. They activate cells in the arcuate nucleus that include the orexigenic neuropeptide Y (NPY) neurons. Ghrelin-responsiveness of these neurons is both leptin and insulin sensitive. Ghrelin also activates the mesolimbic cholinergic-dopaminergic reward link, a circuit that communicates the hedonic and reinforcing aspects of natural rewards, such as food.
Ghrelin levels in the plasma of obese individuals are lower than those in leaner individuals except in the case of Prader-Willi syndrome-induced obesity. Those suffering from the eating disorder anorexia nervosa have high plasma levels of ghrelin compared to both the constitutionally thin and normal-weight controls. These findings suggest that ghrelin plays a role in both anorexia and obesity. Ghrelin levels are also high in patients who have cancer-induced cachexia.
Product Features
- Strip plates and additional reagents allow for use in multiple experiments
- Quantitative protein detection
- Establishes normal range
- The best products for confirmation of antibody array data
Specificity
The capture antibody provided in this kit recognizes human, mouse and rat Ghrelin.
Target Protein Information
Synonyms
Appetite-regulating hormone (Growth hormone secretagogue) (Growth hormone-releasing peptide) (Motilin-related peptide) (Protein M46) [Cleaved into: Ghrelin-28 (Ghrelin) (GHR)]
Gene Names
GHRL MTLRP UNQ524/PRO1066
Application Notes
Kit Components
- Pre-Coated 96-well Strip Microplate
- Wash Buffer
- Standard Peptide
- Assay Diluent(s)
- Biotinylated Peptide
- HRP-Streptavidin
- TMB One-Step Substrate
- Stop Solution
- Assay Diagram
- Positive Control Sample
- Capture Antibody
- User Manual
Other Materials Required
- Distilled or deionized water
- Precision pipettes to deliver 2 µl to 1 ml volumes
- Adjustable 1-25 ml pipettes for reagent preparation
- 100 ml and 1 liter graduated cylinders
- Tubes to prepare standard and sample dilutions
- Orbital shaker
- Aluminum foil
- Saran Wrap
- Absorbent paper
- Microplate reader capable of measuring absorbance at 450nm
- SigmaPlot software (or other software that can perform four-parameter logistic regression models)
Protocol Outline
Prepare all reagents, samples and standards as instructed.
Add 100 µl detection antibody to each well.
Incubate 1.5 h at RT or O/N at 4°C.
Add 100 µl standard or sample to each well.
Incubate 2.5 h at RT.
Add 100 µl prepared streptavidin solution.
Incubate 45 min at RT.
Add 100 µl TMB One-Step Substrate Reagent to each well.
Incubate 30 min at RT.
Add 50 µl Stop Solution to each well.
Read plate at 450 nm immediately.
Storage/Stability
Standard, Biotinylated Ghrelin (GHR) peptide, and Positive Control should be stored at -20°C after arrival. Avoid multiple freeze-thaws. The remaining kit components may be stored at 4°C. Opened Microplate Wells and antibody (Item N) may be stored for up to 1 month at 2° to 8°C. Return unused wells to the pouch containing desiccant pack and reseal along entire edge.