cyclic-gmp and phorbolol-myristate-acetate

Juglone (5-hydroxy-1, 4-naphthoquinone), is a natural phenolic compound that has been shown to relax smooth muscle. Therefore the aim of this study was to determine the effect of juglone on vascular tone using porcine coronary artery (PCA). Segments of PCA, with or without endothelium, were mounted for isometric tension recording in isolated tissue baths and precontracted with the thromboxane A

Topics: Animals; Calcium; Coronary Vessels; Cyclic GMP; Indoles; Ionomycin; Naphthoquinones; Nitric Oxide; Potassium Channel Blockers; Swine; Tetradecanoylphorbol Acetate; Vasoconstriction; Vasodilation; Vasodilator Agents

We investigated the effect of serofendic acid, a neuroprotective substance derived from fetal calf serum, on the morphological changes in cultured cortical astrocytes. Cultured astrocytes developed a stellate morphology with several processes following exposure to dibutylyl cAMP (dbcAMP), a membrane-permeable cAMP analog; 8-Br-cGMP, a membrane-permeable cGMP analog; or phorbol-12-myristate-13-acetate (PMA), a protein kinase C activator. Serofendic acid significantly accelerated the stellation induced by dbcAMP- and 8-Br-cGMP. In contrast, the PMA-induced stellation was not affected by serofendic acid. Next, we attempted to elucidate the mechanism underlying the dbcAMP-induced stellation and explore the site of action of serofendic acid. Both the stellation induced by dbcAMP and the promotional effect of serofendic acid were partially inhibited by KT5720, a specific protein kinase A (PKA) inhibitor. Furthermore, serofendic acid failed to facilitate the stellation induced by Y-27632, an inhibitor of Rho-associated kinase (ROCK). These results indicate that serofendic acid promotes dbcAMP- and 8-Br-cGMP-induced stellation and the promotional effect on dbcAMP-induced stellation is mediated at least partly by the regulation of PKA activity and not by controlling ROCK activity.

Topics: Adrenergic beta-Agonists; Amides; Animals; Astrocytes; Bucladesine; Carbazoles; Cell Shape; Cells, Cultured; Cerebral Cortex; Cyclic AMP-Dependent Protein Kinases; Cyclic GMP; Diterpenes; Dose-Response Relationship, Drug; Drug Synergism; Isoproterenol; Neuroprotective Agents; Pyridines; Pyrroles; Rats; Rats, Wistar; rho-Associated Kinases; Tetradecanoylphorbol Acetate; Time Factors