Dibutyryl-cGMP sodium (Bt2cGMP sodium) is a cell-permeable cGMP analog. Dibutyryl-cGMP sodium preferentially activates cGMP-dependent protein kinase (PKG). Dibutyryl-cGMP sodium inhibits [3H]-arachidonic acid release in human platelets stimulated by gamma
Cholecystokinin type B receptor antagonist PD-136,450 is a partial secretory agonist in the stomach and a full agonist in the pancreas of the rat. Gastrin (cholecystokinin type B (CCK-B)) receptor antagonists may help to elucidate the physiological role o
β-Apooxytetracycline is a potential impurity found in commercial preparations of oxytetracycline. β-Apooxytetracycline is a degradation product formed from oxytetracycline via acid hydrolysis. It has a relative potency of 0.1 compared with oxytetracycline for inhibiting the growth of aerobic sludge bacteria, an MIC50 value of 32 mg/L for tetracycline-sensitive strains of Pseudomonas, and MIC50 values of greater than 32 mg/L for tetracycline-sensitive strains of Agrobacterium, Moraxella, and Bacillus, as well as tetracycline-resistant strains of E. coli. β-Apooxytetracycline (10 mg/kg) is toxic to rats, decreasing body weight, disrupting blood cell counts, and inducing hepatocyte necrosis.
Arachidonic acid is metabolized in the vascular endothelium to epoxytrienoic acids (EETs or EpETrEs) by cytochrome P450 enzymes. The EETs are released in response to acetylcholine, bradykinin, arachidonic acid, or cyclic stretch. (±)14(15)-EET-SI is the methyl sulfonamide analog of 14(15)-EET. This substitution results in a metabolically more stable compound because it is not sensitive to β-oxidation or membrane esterification. (±)14(15)-EET-SI is equipotent to 14(15)-EET in vascular agonist activity as measured by relaxation of precontracted bovine coronary arteries. In addition, 14(15)-EET and the methyl sulfonamide analog both stimulate tyrosine phosphorylation and induce mitogenesis in renal epithelial cells.