Guinea pig ELISA kits for plasma and sera samples are used to study human genes through the guinea pig model (Cavia porcellus), also called the cavy rodent model. After mouzes and rats Guinea pigs are easy in maintained laboratory animals. cDNAs of Guinea pigs are also very popular.Tissue, pathway, proteinase, peptidase, protease ,acrosin, lipoprotein, activator, caspase, trypsin, papain, esterase inhibitors are proteins or receptor ligands or receptor antagonists that bind to an enzyme receptor and decreases its activity. Since blocking an enzyme's activity can kill a pathogen or correct a metabolic imbalance, many drugs are enzyme inhibitors. Not all receptor antagonist that bind to enzymes are inhibitors; enzyme activator ligands or agonists bind to enzymes and increase their enzymatic activity, while enzyme substrates bind and are converted to products in the normal catalytic cycle of the enzyme.