Papaverine hydrochloride

Antiviral Research, 1989, 11(1):15-26.

Comparison of the anti-respiratory syncytial virus activity and toxicity of papaverine hydrochloride and pyrazofurin in vitro and in vivo.[Reference: WebLink]

Based on reports describing their broad antiviral activity, the toxicity and antiviral efficacy of Papaverine hydrochloride and pyrazofurin against respiratory syncytial virus (RSV) infection were tested in vitro in tissue culture cells and in vivo in cotton rats.
METHODS AND RESULTS:
Papaverine inhibited RSV replication in vitro; however, the median minimal toxic dose-median minimal inhibitory concentration ratios (MTD50:MIC50) in vitro and in vivo for papaverine were less than 4. Further work with this compound was discontinued. In contrast, pyrazofurin inhibited RSV replication in vitro (a mean MIC50 of 0.04 microgram/ml was obtained) and in vivo (RSV pulmonary titers were significantly reduced consistently in cotton rats given daily 10 mg/kg doses compared to untreated control animals). However, some toxic effects were observed in both the in vitro and in vivo tests of this compound. The remaining potential of pyrazofurin as an anti-RSV compound is discussed.

Urology, 2008, 72(5):987-990.

Role of Papaverine Hydrochloride Administration in Patients With Intractable Renal Colic: Randomized Prospective Trial.[Reference: WebLink]

To evaluate the therapeutic effect of Papaverine hydrochloride in the treatment of patients with renal colic pain unresponsive to conventional treatment.
METHODS AND RESULTS:
From March 2007 to January 2008, a total of 561 patients with severe renal colic pain due to a ureteral stone were treated with conventional agents (hyoscine-N-butylbromide and diclofenac sodium) in the emergency and urology departments. Of these 561 patients, 110, with no response to the treatment and persistent severe pain, were randomized into 3 groups for additional treatment. The patients in group 1 (n = 37) received intravenous hyoscine-N-butylbromide, those in group 2 (n = 37) received Papaverine hydrochloride, and those in group 3 (n = 36) received pethidine. Before and after treatment, all patients completed a visual analog scale (VAS) questionnaire, with a scale of 0 (no pain) to 10 (maximal complaint), to measure their subjective pain. The mean VAS score of each group was compared with that of the other groups. The pretreatment mean VAS scores of all 3 groups were not significantly different statistically from each other (4.02 ± 1.20, 4.36 ± 1.97, and 4.27 ± 1.50; P > .05). However, after treatment, the mean VAS scores of the patients treated with papaverine (0.93 ± 0.29) and pethidine (0.81 ± 0.38) were significantly different from those of the hycosine group (3.67 ± 2.21; P < .001). However, the mean VAS scores of groups 2 and 3 were comparable (P = .67). Unlike opioids, no papaverine-related severe side effects were observed.
CONCLUSIONS:
Our results indicate that Papaverine hydrochloride can used in an effective manner in the management of renal colic pain in patients unresponsive to commonly used conventional agents.

Immunopharmacology,1993,26(2): 181-185.

Papaverine hydrochloride: effects on HIV replication and T-lymphocyte cell function.[Reference: WebLink]

Papaverine hydrochloride (PAP) has previously been shown to have a potent inhibitory effect on the replication of viruses such as cytomegalovirus (CMV) and measles. In this report the effect of PAP on human immunodeficiency virus (HIV) replication and T lymphocyte cell function were examined.
METHODS AND RESULTS:
MT4 cells infected with HIV strain 3b were incubated with serial dilutions of PAP (1–30 μM). At selected times postinfection HIV replication was measured by reverse transcriptase activity (RT) or HIV p24 Ag. PAP significantly inhibited HIV replication by more than 99% at doses of 30 μM with an CD50 and ED50 of 32 μM and 5.8 μM respectively. The mechanism of inhibition of HIV caused by PAP appeared independent from its ability to increase intracellular levels of cAMP and was not mediated via a direct effect on RT activity. To examine T cell function, peripheral blood mononuclear cells (PBMC) from normal donors were stimulated with phytohemagglutinin (PHA) or CMV Ag in the presence or absence of PAP (1–30 μM). At selected times proliferative response to PHA and CMV Ag were determined by [3H]thymidine uptake. In addition, interferon (IFN) gamma and interleukin 2 (IL2) response to mitogens were measured by radioimmunoassay (RIA). PAP enhanced PHA induced IFN production at doses of 1–10 μM and CMV Ag induced IFN production at doses of 1–3 μM. Higher doses were inhibitory.
CONCLUSIONS:
PAP did not affect IL-2 production or IL2 receptor expression and had an inhibitory effect on mitogenic responses.