Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042963 (vomiting)
 31,883 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

cAMP-specific phosphodiesterase inhibitors display a range of activities in vitro and in vivo which suggest they may be useful in the treatment of inflammatory diseases. However, these compounds elicit a number of side-effects which may limit their therapeutic potential. Certain side-effects of PDE4 inhibitors such as emesis and gastric acid secretion are associated with their actions at a high affinity rolipram binding site (HARBS). In contrast, a number of anti-inflammatory actions of PDE4 inhibitors are better correlated with inhibition of PDE4 catalytic activity than with displacement of [3H] rolipram from HARBS. This suggests that native PDE4s in different cell-types can be discriminated pharmacologically. Although known to be associated with PDE4, the nature of HARBS is uncertain. The majority of evidence suggests it represents particular conformational states of PDE subtypes with which rolipram interacts with high potency (KD approximately 2 nM) (High-affinity PDE4, HPDE4). Rolipram is generally moderately or weakly active (IC50-200 nM-2000 nM) in inhibiting catalytic activity of the majority of crude, partially-purified or recombinant PDE4-preparations (Low-affinity PDE4, LPDE4). Solubilization or V/GSH treatment of particulate eosinophil PDE4, cAMP-dependent kinase activation of RNPDE4D3 and membrane association of HSPDE4A4 increase the potencies of some (e.g., rolipram) but not other (e.g., trequinsin) inhibitors. In eosinophils, the changes in enzyme properties brought about by solubilization result in a close correlation between the potency order of compounds in inhibiting cAMP hydrolysis and displacing [3H] rolipram from HARBS. The identification of distinct pharmacological PDE4 forms may have therapeutic consequences since it may be possible to synthesize potent inhibitors of LPDE4 with low affinity for HARBS which should, theoretically, be less emetic. Most inhibitors synthesized to date (rolipram, denbufylline nitraquazone, etc.) display high-affinity for HARBS but are much weaker in inhibiting cAMP hydrolysis. Other compounds (RP 73401, trequinsin, CDP 840) display slightly higher potency against LPDE4 or do not discriminate between the two putative PDE4 forms. Recently, inhibitors have been synthesized which are considerably more active against LPDE4 than HPDE4. Such compounds with appropriate pharmacokinetic properties may retain anti-inflammatory activity but have a reduced capacity to cause nausea and emesis and, consequently, have a wider therapeutic window than compounds currently undergoing clincial evaluation.
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PMID:Proposal for pharmacologically distinct conformers of PDE4 cyclic AMP phosphodiesterases. 921 22

The synthesis and biological activity of a novel series of 2, 2-disubstituted indan-1,3-dione-based PDE4 inhibitors are described. This structurally unique class of PDE4 inhibitors is markedly different from the known PDE4 inhibitors such as RP 73401 (2) and CDP 840 (3). Structure-activity relationship (SAR) studies led to the identification of inhibitors with nanomolar potency and oral activity in a murine endotoxemia model for TNF-alpha inhibition. Unlike other classical PDE4 inhibitors, several analogues were found to be nonemetic in a canine emesis model at intravenous doses of up to 3 mg/kg.
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PMID:Novel cyclic compounds as potent phosphodiesterase 4 inhibitors. 978 96

The antiemetic efficacy of granisetron, ondansetron and tropisetron was evaluated in patients treated with cisplatin-Adriamycin (CDP/ADM) and ifosfamide (IFO) by continuous infusion (CI). In all, 90 patients with osteosarcoma were randomly assigned to receive granisetron (2 mg/m2), or ondansetron (5.3 mg/m2), or tropisetron (3.3 mg/m2) plus dexamethasone 8 mg/m2. Chemotherapy consisted of CDP (120 mg/m2, 48-h CI) followed by ADM (75 mg/m2, 24-h CI) and then, in the second cycle, delivered 3 weeks later, IFO 15 g/m2 (120-h CI). Complete protection (CP) from emesis was obtained on 59% of the 717 days of treatment, without significant differences among the three study drugs. A significantly higher rate of CP was obtained during chemotherapy with IFO than with CDP/ ADM (69% vs 44%; P<0.0001). The rate of CP declined from the first to the last day of treatment for both CDP/ADM (61% to 27%, P<0.0001) and IFO (95% to 43%) cycles (P<0.0001). When CDP/ ADM and IFO are delivered on multiple days by CI, granisetron, ondansetron and tropisetron have the same antiemetic efficacy, which declines from the first day onward through successive days.
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PMID:Granisetron, tropisetron, and ondansetron in the prevention of acute emesis induced by a combination of cisplatin-Adriamycin and by high-dose ifosfamide delivered in multiple-day continuous infusions. 1073 60