The genome of Drosophila melanogaster has been surveyed for chromosomal regions which exert a dosage effect on the activities of cAMP phosphodiesterase or cGMP phosphodiesterase. Two regions increase cAMP phosphodiesterase activity when present as duplications. A region of the X chromosome increases cAMP phosphodiesterase activity when duplicated and decreases that activity when deficient. This...

       In this study, we investigated the interactive effects of intraperitoneal (i.p.) injections of three different phosphodiesterase inhibitors (PDEIs) on morphine-induced analgesia in mice using tail-flick method. Subcutaneous administration of morphine (1, 3 and 6 mg/kg) caused significant antinociceptive effects in a dose dependent manner. Administration of pentoxifylline (12.5, 25, 50 an...

Retinoic acid decreases proteinuria and glomerulosclerosis in several animal models of kidney disease by protecting podocytes from injury. Our recent in vitro studies suggest that all-trans retinoic acid induces podocyte differentiation by activating the retinoic acid receptor-α (RARα)/cAMP/PKA/CREB pathway. When used in combination with all-trans retinoic acid, an inhibitor of phosphodiesteras...

Long-term regulation of the cyclic nucleotide phosphodiesterase of the C-6 rat glioma cell line has been studied. Both the low K(m) and high K(m) activities can be induced by elevation of intracellular cyclic AMP levels following either dibutyryl cyclic AMP or norepinephrine treatment of the cells. The enzymes are maximally induced by 3-4 hr. The presence of either cycloheximide or actinomycin ...

1. A spectrophotometric assay of 2':3'-cyclic nucleotide 3'-phosphodiesterase (EC 3.1.4.37) based on the use of an acid-base indicator and a buffer having identical PKa values is described. The assay is sinmple and rapid; it was particularly convenient for monitoring the enzyme activity at vat :ous stages of purification. 2. Several proteinases were examined for their ability to solubilize 2':3...