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PubMed2002

Effects of the I(Kr)-blocking agent dofetilide and of the I(Ks)-blocking agent chromanol 293b on regional disparity of left ventricular repolarization in the intact canine heart.

Recent in vitro studies have described regional differences of ion current expression and function, possibly accounting for reduced homogeneity of repolarization in the heart. In 11 intact canine hearts regional disparity of repolarization was determined at baseline and after administration of the I(Kr) blocking agent dofetilide (30 microg/kg) and the I(Ks)-blocking agent chromanol 293b (10 mg/kg). Effective refractory periods (ERPs) were determined through up to 10 needle electrodes inserted into basal, midwall and apical regions of the left ventricular wall using the extrastimulus technique (cycle length [CL] 300 and 850 ms). At baseline (CL of 850 ms), ERPs were significantly longer in epicardial muscle layers of the apex compared to the base. In deeper muscle layers regional differences of ERPs were not detectable. Administration of dofetilide increased apico-basal disparity of repolarization, due to a more marked increase of ERPs in the apex than in the base. In contrast, homogeneous ERPs were evident along the apico-basal axis after administration of chromanol 293b. Transmural dispersion of refractoriness could not be observed in any region at baseline, or after drug-administration. In the intact canine heart, apico-basal disparity of repolarization varies between individual muscle layers. Dependent on their current specificity, antiarrhythmic agents may enhance or diminish regional disparity of repolarization.

Action Potentials↗

PubMed1986

BW A256C, a chemically novel class 1 antiarrhythmic agent. A comparison of in vitro and in vivo activity with other class 1 antiarrhythmic agents.

BW A256C (5(3)-amino-6-(2,3-dichlorophenyl)-2,3(2,5)-dihydro-3(5)-imino-2 -isopropyl-1,2,4-triazine) is a novel class 1 antiarrhythmic agent designed to combine the features of potency with reduced central nervous system penetration. BW A256C reduced the maximum rate of depolarization of guinea-pig ventricle and dog Purkinje fibres in vitro (EC50, 2.2 X 10(-6) M and 1.8 X 10(-6) M, respectively), being significantly more potent than quinidine, lidocaine, disopyramide and flecainide. BW A256C was also more potent than these agents at inhibiting aconitine-induced arrhythmias in anaesthetized rats; however, unlike these agents, BW A256C was devoid of hypotensive activity at antiarrhythmic doses. In anaesthetized dogs, intravenous administration of BW A256C (0.25-1 mg kg-1) caused a dose-dependent suppression of ventricular arrhythmias that occurred on reperfusion of an occluded coronary artery. In conscious dogs, intravenous infusion (total dose, 1.5 mg kg-1) or oral administration of BW A256C (1.25-5 mg kg-1) caused dose-dependent suppression of the ventricular ectopic activity that occurred following 20-24 h of permanent coronary artery ligation. In the conscious dog, BW A256C was approximately 7 times more potent and was also longer acting than flecainide. Administration of BW A256C was not associated with any evidence of peripheral or CNS toxicity. However, plasma levels 3-4 times greater than the antiarrhythmic levels were associated with a proarrhythmic activity.

Aconitine↗

PubMed2005

Susceptibility of Neisseria meningitidis to 16 antimicrobial agents and characterization of resistance mechanisms affecting some agents.

Neisseria meningitidis represents a pathogen of great public health importance in both developed and developing countries. Resistance to some antimicrobial agents used either for therapy of invasive infections or for prophylaxis of case contacts has long been recognized, although specific guidelines for susceptibility testing have not been fully developed. We have examined the susceptibilities of a collection of 442 meningococcal clinical isolates from 15 countries to 16 antimicrobial agents. These included isolates recovered between 1917 and 2004, with representatives of all major serogroups. All isolates were tested by the Clinical and Laboratory Standards Institute (formerly NCCLS) broth microdilution method using Mueller-Hinton lysed horse blood broth, while a subset of 102 isolates was tested by agar dilution using Mueller-Hinton sheep blood agar. Most isolates provided adequate growth for MIC determinations by both broth and agar methods. Growth in broth was enhanced by CO(2) incubation and was required for two strains (1.7%). MICs of the study drugs compared favorably between the broth and agar methods (79 to 100% essential agreement), and MICs also generally agreed closely (92 to 100% essential agreement, excluding azithromycin) between broth tests incubated in the two different atmospheres. Elevated penicillin and ampicillin MICs (> or =0.12 microg/ml and > or =0.25 microg/ml, respectively) occurred in 14.3% and 8.6% of strains and were associated with polymorphisms of the penA gene encoding a modified penicillin-binding protein 2. None of the 442 isolates produced beta-lactamase. Elevated tetracycline and doxycycline (but not minocycline) MICs were associated with efflux-mediated resistance encoded by tet(B) in 13 strains. Resistance to sulfisoxazole in 21.7% of strains and to trimethoprim-sulfamethoxazole in 21.0% resulted from polymorphisms of folP encoding a modified dihydropteroate synthetase. Seven strains were resistant to rifampin due to mutations in the rpoB gene, and two strains were resistant to chloramphenicol due to production of chloramphenicol acetyltransferase mediated by catP. Two strains had reduced quinolone susceptibility due to mutations of gyrA. The determination of the susceptibilities of a large group of meningococcal strains (including strains with characterized resistance mechanisms) to 16 antimicrobial agents has served as the essential first step in defining susceptibility testing breakpoints specific for this organism.

Anti-Bacterial Agents↗

PubMed2001

Antifibrinolytic agents and desmopressin as hemostatic agents in cardiac surgery.

OBJECTIVE: To review the use of systemic hemostatic medications for reducing bleeding and transfusion requirements with cardiac surgery. DATA SOURCES: Articles were obtained through computerized searches involving MEDLINE (from 1966 to September 2000). Additionally, several textbooks containing information on the diagnosis and management of bleeding associated with cardiac surgery were reviewed. The bibliographies of retrieved publications and textbooks were reviewed for additional references. STUDY SELECTION: Due to the large number of randomized investigations involving systemic hemostatic medications for reducing bleeding associated with cardiac surgery, the article selection process focused on recent randomized controlled trials, metaanalyses and pharmacoeconomic evaluations. DATA EXTRACTION: The primary outcomes extracted from the literature were blood loss and associated transfusion requirements, although other outcome measures such as mortality were extracted when available. DATA SYNTHESIS: Although the majority of investigations for reducing cardiac bleeding and transfusion requirements have involved aprotinin, evidence from recent meta-analyses and randomized trials indicates that the synthetic antifibrinolytic agents, aminocaproic acid and tranexamic acid, have similar clinical efficacy. Additionally, aminocaproic acid (and to a lesser extent tranexamic acid) is much less costly. More comparative information of hemostatic agents is needed retative to other outcomes (eg., reoperation rates, myocardial infarction, stroke). There is insufficient evidence to recommend the use of desmopressin for reducing bleeding and transfusion requirements in cardiac surgery, although certain subsets of patients may benefit from its use. CONCLUSIONS: Of the medications that have been used to reduce bleeding and transfusion requirements with cardiac surgery, the antifibrinolytic agents have the best evidence supporting their use. Aminocaproic acid is the least costly therapy based on medication costs and transfusion requirements.

Aminocaproates↗

PubMed1994

Effects of KW-5805, a new antiulcer agent, on experimental gastric and duodenal ulcers, gastric mucosal lesions by necrotizing agents and gastric acid secretion.

Effects of KW-5805, a new antiulcer agent, on various experimental ulcers, necrotizing agent-induced gastric lesions and gastric acid secretion in rats were compared with those of pirenzepine and cimetidine. KW-5805 showed antiulcer activities against experimental gastric and duodenal ulcers (ED50 = 1.2-10.0 mg/kg, p.o.). KW-5805 effectively inhibited gastric lesions induced by various necrotizing agents (ED50 = 4.5-39.8 mg/kg, p.o.). In addition, the cytoprotective effect of KW-5805 was not affected by indomethacin, but reserved by N-ethylmaleimide. These antiulcer and cytoprotective effects of KW-5805 were more potent than those of pirenzepine and cimetidine. In pylorus-ligated rats, intraduodenal KW-5805 administration at 30 mg/kg showed a weak antisecretory effect, which was 3-10 times less potent than those of pirenzepine and cimetidine. In rats with acute gastric fistula, intravenous injection of KW-5805 reduced methacholine-stimulated gastric acid secretion at doses of 10 and 30 mg/kg and inhibited tetragastrin-induced acid secretion at 30 mg/kg. These results indicate that KW-5805 has potent and broad antiulcer properties, which are probably exerted by its potent cytoprotective effect in addition to its antisecretory effect.

Animals↗

PubMed1998

Central nervous system effects of the novel antiallergic agent HSR-609 and typical antiallergic agents using behavioral and electroencephalographic analyses in dogs.

We studied the central nervous system (CNS) effects of 3-[4-(8-fluoro-5, 11-dihydrobenz[b] oxepino[4, 3-b]pyridin-11-ylidene)piperidino]propionic acid dihydrate (HSR-609), a novel amphoteric antiallergic agent having antihistaminic activity. Its effects on gross behavior, spontaneous electroencephalograms (EEG) and some pharmacological parameters of unanesthetized, unrestrained dogs with chronic indwelling brain electrodes after oral administration were compared with typical antiallergic agents and 8-fluoro-5, 11-dihydro-11-(1-methyl-4-piperidylidene)benz[b] oxepino[4,3-b]pyridine (PY-608), a non-amphoteric basic compound having a similar chemical structure to HSR-609. HSR-609 (1, 10 and 100 mg/kg) and terfenadine (100 mg/kg) had no effect on the behavior, EEG patterns, sleep-wakefulness cycles or EEG power spectrum. Cyproheptadine (10 mg/kg), ketotifen (30 mg/kg) and PY-608 (10 mg/kg) increased slow waves with high amplitude in all EEG leads and caused dissociation between the slowing of EEG and waking behavior. Both azelastine (30 mg/kg) and oxatomide (100 mg/kg) caused generalized seizure discharges accompanied by agitation with the former and sedation with the latter. These findings suggest that observations of behavior and EEG in conscious dogs can be useful for clarifying the pharmacological characteristics of various antiallergic agents on the CNS. We were able to show that HSR-609 has no effect on the behavior and EEG of dogs because of its amphoteric chemical structure.

Animals↗

PubMedDate not supplied

Advances in chemotherapy for small cell lung cancer: single-agent activity of newer agents.

Small cell lung cancer (SCLC) is a common neoplasm with an extremely poor prognosis. Patients with extensive-stage disease have a 5-year survival rate of 1% to 2%. Identification of new active chemotherapy agents is of great importance for the development of more effective treatment for SCLC. Several new drugs that have established a role in the management of non-SCLC in the past decade are also active in SCLC. The mean response rates in untreated versus previously treated patients for these newer drugs are: 26% versus 14% for vinorelbine, 27% versus 14% for gemcitabine, 45% versus 29% for paclitaxel, 22% versus 25% for docetaxel, 39% versus 19% for topotecan, and 50% versus 16% to 24% for irinotecan. A comparison of the response rates of those agents to more established drugs (e.g., cisplatin and etoposide) suggests that the newer drugs are equally or more active in previously treated patients with SCLC. This activity is even more impressive because initial therapy during the past decade has almost always included platinum and/or an epipodophyllotoxin in the regimen. Furthermore, a recent randomized trial showed that the combination of a newer agent (irinotecan) with cisplatin was superior to a standard etoposide and cisplatin regimen in patients with newly diagnosed extensive-stage SCLC. These data support further evaluation of the newer chemotherapeutic drugs, and especially the camptothecins (irinotecan and topotecan) and the taxanes (paclitaxel and docetaxel), in the initial treatment of SCLC.

Antineoplastic Agents↗

PubMed2002

Effects of nonsteroidal anti-inflammatory agents (NSAIDs) on ovarian carcinoma cell lines: preclinical evaluation of NSAIDs as chemopreventive agents.

PURPOSE: Nonsteroidal anti-inflammatory agents may inhibit carcinogenesis in specific tissues including the colon, breast, and pancreas, and, hence, may prove to be effective chemopreventive agents. The purpose of this study was to investigate the cellular effects of acetylsalicylic acid (ASA), acetaminophen, and a COX-2 inhibitor (NS-398) on the growth of cell lines of human ovarian cancer in vitro. EXPERIMENTAL DESIGN: SK-OV-3, Caov-3, and NIH:OVCAR-3 ovarian carcinoma cell lines were treated with ASA (10(-6) M-10(-2) M), acetaminophen (10(-6) M-10(-2) M), and a COX-2 inhibitor (10(-6) M-10(-4) M) for 96 h. The number of viable cells was determined using a tetrazolium conversion assay. Immunohistochemical assessment was performed for alterations in expression of Ki-67, erbB-2, COX enzyme, and apoptosis in primary ovarian cancer cells using terminal deoxynucleotidyl transferase (Tdt)-mediated nick end labeling assay. RESULTS: A decrease in cell number compared with controls was observed for all of the cell lines treated with ASA, acetaminophen, and COX-2 inhibitor by cell count and tetrazolium conversion assay. A significant decrease in Ki-67 compared with controls in the OVCAR-3 (P = 0.005) and SK-OV-3 (P = 0.007) cell lines after treatment with the COX-2 inhibitor was observed. We observed a decrease in mitotic activity compared with controls in each cell line after treatment with the COX-2 inhibitor. Apoptosis was observed in primary ovarian cancer cell culture treated with COX-2 inhibitor. CONCLUSION: Our results suggest additional study for the use of nonsteroidal anti-inflammatory agents, specifically COX-2 inhibitors, as a strategy of chemoprevention for ovarian cancer.

Acetaminophen↗

PubMedDate not supplied

Response of human pulp capped with a bonding agent after bleeding control with hemostatic agents.

PURPOSE: This study evaluated the response of human pulps capped with a bonding agent after bleeding control with different hemostatic agents. MATERIAL AND METHODS: Twenty-five Class II cavities were prepared in 25 caries-free human premolars scheduled for extraction due to orthodontic treatment. The pulp exposures were performed on the occlusal floor. The teeth were randomly divided into five groups. Groups 1-4 were capped with an adhesive system after hemostasis with different agents: Group 1--saline solution; 2--ferric sulfate; 3--2.5% NaOCl; 4--Ca(OH)2 solution. In Group 5, after hemostasis with saline solution, the pulp was capped with calcium hydroxide (control group). Then, ScotchBond Multi Purpose Plus was applied and the resin composite Z-100 placed incrementally according to the manufacturers' directions. After 60 days, the teeth were extracted and processed for light microscopic examination (HE) and the groups were categorized in a histological score system. The data were subjected to a non-parametric test (alpha=0.05). RESULTS: Overall, the histological features showed that the pulp response from Groups 1 through 4 was inferior to the response from Group 5, where dentin bridging occurred. In all groups, where the adhesive system was used for capping, the pulp response varied from an acute inflammatory, with varying degrees, to necrosis. No dentin bridge was formed after adhesive capping.

Adolescent↗

PubMedDate not supplied

Evaluation of N-4-(hydroxycarbophenyl) retinamide as a cancer prevention agent and as a cancer chemotherapeutic agent.

In this review, a retinoid analogue (N-4-hydroxycarbophenyl) retinamide (R11) has been evaluated for its pharmacological and clinical properties. R11 has been studied both as a cancer prevention agent, as well as, a cancer chemotherapeutic agent. R11 alone and in combination with other agents can be used for the treatment of cervical dysplasia or leukemia. This review will examine novel strategies and mechanisms of action for retinoids in the treatment and prevention of cancer.

Animals↗

PubMed1988

Lexitropsins: rational design of DNA sequence reading agents as novel anti-cancer agents and potential cellular probes.

Alternative approaches to the problem of developing DNA sequence-specific agents for potential use in diagnosis and therapy of cancer are reviewed. The major problems of oligonucleotide probes, i.e. difficulty of cellular uptake and susceptibility to intracellular degradation, suggested as possible alternatives the employment of certain oligopeptide agents. Progress in the development of lexitropsins, or information-reading oligopeptides, which bind selectively to the minor groove of duplex nucleic acids, is discussed. The ability to engineer lexitropsins to recognize and bind to predetermined sequences, the ready cellular uptake and concentration in the cell nucleus may offer advantages in the development of cellular regulatory agents. The anti-cancer efficacy of prototype sequence-specific minor groove alkylators is described.

Antineoplastic Agents↗

PubMed1983

Potentiation of DNA-reactive antineoplastic agents and protection against S-phase-specific agents by anguidine in Chinese hamster ovary cells.

Anguidine, a protein synthesis inhibitor, has been shown to induce a reversible cell cycle arrest in exponentially growing Chinese hamster ovary cells. The effect of pretreatment with anguidine on the cytotoxicity of subsequently administered various chemotherapeutic agents, hyperthermia, and radiation was investigated. We found that anguidine greatly potentiated the cytotoxic activity of cis-dichlorodiammineplatinum(II) and melphalan by abolishing the initial shoulder and steepening the subsequent exponential portion of the survival curves. Bleomycin-induced cell kill was also potentiated by anguidine pretreatment but to a lesser extent. However, anguidine pretreatment did not substantially alter radiation cytotoxicity. In contrast, anguidine markedly reduced the lethal effect of hydroxyurea, 5-fluorouracil, and hyperthermia, three modalities with S-phase activity. To investigate whether both anguidine-induced potentiation and protection of cells by different antitumor agents were due to its induction of complete suspension of cycle traverse, experiments were also conducted with plateau-phase cultures. Whereas anguidine potentiated cis-dichlorodiammineplatinum(II) cytotoxicity in an identical fashion as noted in exponentially growing cells, its protective effect against lethal damage from Adriamycin was absent. Thus, it appears that the two opposite effects of anguidine modification of cell kill by cytotoxic agents (protection and potentiation) come about by two different mechanisms, with cell cycle arrest underlying cytoprotection and the mechanism of synergistic toxicity remaining obscure.

Animals↗

PubMed1993

[In vitro activity of chemotherapeutic agents on the most common bacterial agents causing urinary infections].

The authors made an investigation of the contemporary position as regards the effectiveness of chemotherapeutic agents used for treatment of infections of the urinary pathways caused by the most frequently found infectious agents in out-patients, small Prague hospitals and the University hospital in Prague-Motol. The dominating infectious agent causing urinary infections remains E. coli. A serious feature is the increase of enterococcal infections in hospitals. As to the antibacterial effect, a dominant position is held by furantoin, in enterococcal infections in hospitals. high antibacterial activity of fluoroquinolones is, however, also associated with the responsibility to use them rationally.

Anti-Infective Agents, Urinary↗

PubMed1976

Susceptibility of Prototheca species to antifungal agents.

Twenty isolates of Prototheca filamenta, Prototheca moriformis, Prototheca stagnora, Prototheca wickerhamii, and Prototheca zopfii were tested for in vitro susceptibility to five commonly used antifungal agents: amphotericin B, 5-fluorocytosine, griseofulvin, miconazole, and nystatin. The results revealed resistance to griseofulvin of all the Prototheca isolates tested and an inhibitory effect on P. filamenta by high 5-fluorocytosine concentrations (minimal inhibitory concentration [MIC] = 12.5 to 100 mug/ml; minimal fungicidal or algacidal concentration [MFC/MAC] = 50 to 100 mug/ml). P. filamenta isolates were also susceptible to miconazole (MIC = 0.1 to 0.5 mug/ml, MFC/MAC = 0.5 to 1 mug/ml); isolates of the other Prototheca species varied in regard to miconazole activity from susceptible to resistant (MIC = 1 - >100 mug/ml, MFC/MAC = 5 - >100 mug/ml). The Prototheca isolates revealed an in vitro susceptibility to the polyene antifungal agents, amphotericin B, and nystatin (MIC = 0.09 to 3.12 mug/ml and 0.19 to 12.5 mug/ml, respectively; MFC/MAC = 0.19 to 25 mug/ml and 0.75 to 25 mug/ml, respectively).

Amphotericin B↗

PubMedDate not supplied

Ineffectiveness of inicarone, a fibrinolytic agent, alone or in combination with chemotherapeutic agents on spontaneously metastasizing murine tumours.

The effect of inicarone (L7035), a potent fibrinolytic, alone or in combination, was investigated on spontaneously metastasizing Lewis lung carcinoma (implanted intramuscularly) to verify whether it could prevent the formation of metastases. After intraperitoneal and oral administration, inicarone did not show any cytotoxicity since the survival of animals was not prolonged. Its activity was compared to that of warfarin, an anticoagulant: both drugs were inactive when administered in curative treatment and inicarone even enhanced the number of lung metastases. When administered in combination with cyclophosphamide, an antiproliferative agent, inicarone did not induce any synergism or antagonism, but this combination did not inhibit tumour growth or metastasis spreading. Moreover, when inicarone was combined with a potent antimetastatic agent, Nocodazole, it was shown to be in competition with the latter agent and totally overshadowed its activity; since inicarone had no antimetastatic effect, the number of metastases rose dramatically.

Animals↗

PubMed1983

Hemodynamic and electrocardiographic effects in man of a new nonionic contrast agent (iohexol): advantages over standard ionic agents.

Iohexol is a new, nonionic contrast material that has been shown in animal studies to hold great promise as an agent for coronary arteriography and ventriculography with fewer adverse hemodynamic effects than standard ionic media. At present, it has not been studied systematically in man. Fifty patients referred for elective cardiac catheterization were randomized to receive either iohexol or meglumine sodium diatrizoate (Renografin-76). Both operator and patient were blinded as to which agent was being used. Hemodynamic variables measured were pulmonary artery wedge pressure and systemic blood pressure. In addition, the following electrocardiographic indexes were evaluated: S-T segment shifts, changes in Q-T interval, changes in T-wave amplitude, and changes in heart rate. These variables were measured after left ventriculography and after both left and right coronary arteriography. Both iohexol and sodium meglumine diatrizoate produced small transient elevations in pulmonary artery wedge pressure. Systemic hypotension occurred with both agents but was more profound and longer-lasting with sodium meglumine diatrizoate. Iohexol injection resulted in no electrocardiographic changes, whereas sodium meglumine diatrizoate produced marked Q-T prolongation, as well as changes in T-wave amplitude and heart rate. Iohexol was well tolerated by the patients, and radiographic opacification was good to excellent in all cases. Thus, iohexol produces fewer deleterious hemodynamic and electrocardiographic changes than sodium meglumine diatrizoate when studied in a typical adult population requiring diagnostic cardiac catheterization. This favorable preliminary experience in man has potential widespread importance because of the large number of patients undergoing angiographic procedures.

Aged↗

PubMed1990

Safety of cardiac angiography with conventional ionic contrast agents. The Philadelphia Area Contrast Agent Study.

To characterize the frequency of adverse reactions to conventional ionic contrast agents, data describing the frequency of such reactions were gathered from 4,630 diagnostic cardiac angiographic procedures. The patient population had a large prevalence of severe or unstable cardiac disease (56% had New York Heart Association class III, IV or V, 12.6% had left ventricular end-diastolic pressure greater than 25 mm Hg and 34% had 3-vessel or left main coronary artery disease). The overall minor adverse reaction rate was 14.2%. Major adverse reactions (requiring treatment) occurred in 61 (1.3%) of procedures. All adverse reactions were managed successfully and there were no deaths. Adverse reactions were more frequent in patients with higher New York Heart Association classes and with elevated left ventricular end-diastolic pressure. The adverse reaction rate was not increased in patients with more extensive coronary artery disease, reduced left ventricular ejection fraction or reduced cardiac index. The overall adverse reaction rate was probably influenced by physician behavior. Smaller volumes of contrast agent were administered to patients with more severe cardiac disease. Six percent of procedures were abbreviated either because of an adverse reaction or of concern that a reaction might occur if the procedure were continued. As a result, the diagnostic data obtained were judged to be inadequate in 0.8% of procedures. These data demonstrate that appropriate operator caution within the highly monitored environment of the cardiac catheterization laboratory allows cardiac angiography to be performed safely with conventional ionic contrast agents in most patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1979

Augmentation of the in vitro humoral immune response by pharmacologic agents. I: An explanation for the differential enhancement of humoral immunity via agents that elevate cAMP.

Agents that elevate intracellular concentrations of cAMP in cultured spleen cells can augment the in vitro 19s humoral immune response to SRBC. DBcAMP and 8BrcAMP were more effective than MIX, CT, PGE1, or ISO in producing the enhanced PFC response, when they were present only during an early stage of immune induction. The thesis is presented that the differential ability of these agents to augment humoral immunity results from their relative ability to maintain elevated concentrations of intracellular cAMP. Studies on the cellular mechanism by which cAMP elevation produces immune enhancement reveal that DBcAMP effects are on a T-cell-deficient population of murine spleen cells (predominantly B cells and macrophages). In addition, we showed that DBcAMP cannot replace the need for helper T cells in the induction of the PFC response to SRBC. Taken collectively, these results suggest that cAMP may be an important immunoregulatory signal, and that a variety of pharmacologic agents that modulate the induction of the humoral immune response may operate via this as a final common biochemical pathway.

1-Methyl-3-isobutylxanthine↗