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Ferula hermonis Boiss. (Apiaceae), commonly known as 'Shilsh-el-zallouh', 'Hashishat-al-kattira' or 'The Lebanese viagra', is a small shrub that grows abundantly on the Hermon Mountain between Syria and Lebanon. The seeds and roots of this plant have long been used in the Middle East as an aphrodisiac, and for the treatment of frigidity and impotence for both men and women. The antiinflammatory properties of three major daucane esters, ferutinin (1) teferin (2) and teferidin (3), isolated from the root oil of Ferula hermonis, were assessed by the carrageenan-induced oedema model in rats. The antiinflammatory effect of both 1 and 2 was observed with a dose of 100 mg/kg, while compound 3 did not show any antiinflammatory activity; conversely it produced a significant proinflammatory effect 2 and 3 h after carrageenan injection.

The Nobel Prize winning discovery of nitric oxide (NO) in 1986 was the starting point for a new innovation in drug discovery. NO acting as a mediator at different physiological systems is believed to be involved in many physiological and pathological conditions through the formation of the second messenger cyclic guanosine monophosphate (cGMP). cGMP-dependent vasodilation effect of NO is important in regulating pulmonary and systemic pressures, maintaining penis erection, preventing atherosclerosis, preventing platelet aggregation, and protecting and controlling cardiac functions. The main enzyme involved in the termination of cGMP effects is phosphodiesterase enzyme 5 (PDE-5), which is overexpressed in ventricular hypertrophy and heart failure. A milestone in drug discovery was the selective inhibitors of PDE-5 that developed to be a multibillion dollar blockbuster in drug market. PDE-5 inhibitors are approved for the treatment of erectile dysfunctions (EDs), pulmonary hypertension, and benign prostatic hypertrophy. They are also under clinical trials for their cardiac protection against damage induced by ischemia or heart failure. This review article is an update about the pharmacotherapeutics of PDE-5 inhibitors and the majestic history that led to their discovery. The information reported in this review was obtained from the electronic sources of different databases such as PubMed Central, Google Scholar, and Scopus. Keywords used for search included cGMP (mechanisms and functions), EDs (drugs used), nitric oxide, and PDE-5 inhibitors (clinical applications). A total of 165 articles were studied, of which 45 articles were referred to in this review.

ObjectivesStudies regarding the role of gamma aminobutyric acid (GABA) in depression are conflicting. Therefore, it was decided to examine the effect of different drugs that enhance the GABA system on the time of immobility induced by the forced swim test (FST).Materials and methodsAdult albino mice were divided into several groups of six animals. Each group received an intraperitoneal injection of either imipramine (10, 20, or 30 mg/kg), diazepam (0.5, 1, or 2 mg/kg), vigabatrin (100, 200, or 300 mg/kg), zolpidem (2.5, 5, or 10 mg/kg), or alprazolam (1, 2.5, or 5 mg/kg). Control groups received the appropriate vehicle. One hour after injection, the duration of immobility was measured for 5 min in the FST. The percentage change in the duration of immobility from the control was calculated for each group. The statistical test of the difference between the treated and the control groups was calculated using unpaired Student's t-test.ResultsImipramine produced a significant dose-dependent decrease in the duration of immobility (78, 74, and 56%, respectively). Different doses of diazepam, vigabatrin, and zolpidem produced a significant increase in the duration of immobility (119, 126, and 128%), (116, 124, and 128%), and (108, 109, and 119%), respectively. The two low doses of alprazolam produced a significant increase (115 and 120%), while the high dose produced a significant decrease in the duration of immobility (74%).ConclusionIncreasing central GABAergic activity by different mechanisms has resulted in a depressant-like activity measured as an increase in the duration of immobility in the FST model of depression.

BackgroundCombination analgesics provide more effective pain relief for a broader spectrum of pain. This research examines the possible potentiation of the analgesic effect of different classes of antidepressants when combined with aspirin in thermal model of pain using Albino mice.MethodsDifferent groups of six animals each were injected intraperitoneally by different doses of aspirin (50, 100, or 200 mg/kg), imipramine (2.5, 7.5, 15 or 30 mg/kg), fluoxetine (1.25, 2.5, 5 or 7.5 mg/kg), mirtazapine (1.25, 2.5, or 5 mg/kg) and a combination of a fixed dose of aspirin (100 mg/kg) with the different doses of the three antidepressants. One hour later the analgesic effect of these treatments were evaluated against thermally induced pain. All data were subjected to statistical analysis using unpaired Student's t-test.ResultsAspirin had no analgesic effect in thermally induced pain. The three selected antidepressants produced dose dependent analgesia. The addition of a fixed dose of aspirin to imipramine significantly increased the reaction time (RT) of the lowest dose (by 23%) and the highest dose (by 20%). The addition of the fixed dose of aspirin to fluoxetine significantly increased RT by 13% of the dose 2.5 mg/kg. Finally, the addition of the fixed dose of aspirin significantly potentiated the antinociceptive effect of the different doses of mirtazapine (RT was increased by 24, 54 and 38% respectively).ConclusionCombination of aspirin with an antidepressant might produce better analgesia, increasing the efficacy of pain management and reduces side effects by using smaller doses of each drug.