Pharmaceutical Sciences
Volume:19 Issue: 3, 2013

Opioids exert different effects on seizure threshold based on their doses and the models. P-glycoprotein (p-gp) prevents various substances from entering the brain. Morphine is a p-gp substrate. The aim of this study was to investigate the effects of morphine on strychnine-induced convulsion in ovariectomized mice and to see whether verapamil as a p-gp pump inhibitor interferes with that effects. Female mice were ovariectomized to remove the gonadal sex hormones Thirty minutes prior to induction of convulsion by subcutaneous injection of strychnine, the animals were received morphine (1, 2, 3mg/kg), naloxone (1, 2, 5mg/kg), verapamil (20mg/kg) and morphine (3mg/kg)+verapamil (20mg/kg) intraperitoneally. Then, the onset of convulsion and time to death were recorded. The significance of differences for the seizure parameters were assessed using one-way analysis of variance (ANOVA) followed by least significant difference (LSD) post hoc comparison or unpaired t-test. The results showed that morphine produced anticonvulsant effect by prolonging the time to death (P < 0.001) and naloxone had no effect on strychnine-induced convulsion. Verapamil alone had no effect on the convulsion whereas, it significantly (p < 0.05) reduced the anticonvulsant effect of morphine by reducing the time to death. Anticonvulsant activity of morphine is mediated through different mechanisms. The reduced anticonvulsant effect of morphine by verapamil seems to be because of increase in morphine concentration in brain.

Pulegone is an allelochemical widely occurring in plants of the Labiatae family. Pulegone has a pleasant mint like odor and therefore is used, directly or as a constituent of a variety of essential oils, in beverages and processed foods for human consumption. To evaluate the antidiarrheal activity of pulegone using various pharmacological models, the intestinal transit, castor oil induced diarrhea and enteropooling methods were used in this study. The acute toxicity and lethality of pulegone was determined using the Lorke’s method. The pulegone was practically nontoxic administered p.o. The LD50 was 570 mg/kg given p.o. Pulegone (25–100 mg/kg, p.o.) produced insignificant reduction in propulsive movement in the normal and significant (P < 0.05) reduction in castor oil induced intestinal transit tests in rats. Peak effect was elicited at 25 mg/kg but this effect was higher than that produced by loperamide (3 mg/kg, p.o.). In the castor oil induced diarrhea test, high dose of pulegone significantly delayed the onset but did not decrease the frequency and severity of diarrhea. Pulegone at the dose of 25 mg/kg significantly reduced the volume of intestinal secretion induced by castor oil but produced no effect on diarrhea parameters. The results obtained in this study suggest that the pulegone did not possess antidiarrheal property due to weak inhibition of gastrointestinal propulsion and fluid secretion.

Vitamin E is a fat–soluble agent protecting cells from free radicals damages. Previous studies have shown that oxidative stress plays an important role in mucosal intestinal damages in burn trauma. This study aimed to investigate vitamin E effects on small intestinal mucosal changes in burned rats. Mature male rats (n=32) weighing 260 ± 10 g were used in this experiment. After induction of deep general anesthesia, a determined area of rats’ back region (10% of body surface) was exposed to 95oC water for 8 seconds to induce a second-degree wet burn. The evaluated groups in our study were: 8 rats without burning, 8 rats without burning treated with vitamin E, 300 mg/kg/day for 15 days, 8 burned rats without medication and 8 burned rats treated with vitamin E, 300 mg/kg/day for 15 days. All rats were killed on fifteenth day by ether inhalation. The samples were taken from the first part of small intestine and were stained by Hematoxylin & Eosin method. Burned rats receiving vitamin E had a higher intestinal villi height and lower intestinal lumen diameter as compared to burned rats without the vitamin E treatment (P < 0.05 and P < 0.01, respectively) and those values were close to the results of unburned ones. There were no significant differences among the study groups regarding the intestinal diameter and muscular layer thickness. Vitamin E can improve intestinal villus height and lumen diameter and its consumption at the time of burning may protect intestine mucosa.

Oral Contraceptive pills (OCPs) are one of the most common used ways for preventing unwanted pregnancies, but in order to guarantee a higher rate of success, correct usage is essential. The present study aimed to examine the level of knowledge, attitude and practice of the OCPs users. Two hundred women who received their OCP from a local health center (group 1; n=?) or from a pharmacy (group 2; n=) were questioned according a pre-designed questionnaire. The questionnaire consisted of questions regarding the demographic information, correct usage of OCPs, their side effects, contraindications, non-contraceptive benefits, and some myth-based questions. The rates of correct answers were compared between the two groups using t-test. The most commonly used OCP was LD (low dose) contraceptive. The rate of previous unwanted pregnancies for group 1 and 2 was 35 and 24%, respectively. The subjects in group 1 were counseled extensively on the proper use of the contraceptive, and no counseling was performed with the subjects in group 2. The level of knowledge outweighed the level of counseling provided to the subjects. Regarding the information and consultation that were given to the subjects by their health services, the subjects'' knowledge on the proper use of the oral contraceptive pills was high but not to an extent that would be. The results of this study suggest that health services, especially pharmacies should provide more information and consultation about OCPs for their clients.

Pseudomonas aeruginosa is an opportunistic human pathogen. This organism is thought to persist by forming biofilm within human infections. Bacteria growing in biofilm exhibits increased resistance to antimicrobial agents. In this study, we examined the effect of oxygen on the development of biofilm by P. aeruginosa and on the level of its resistance to the antibiotics. The P. aeruginosa control strain group and 45 clinical isolates were cultured and antibiotic susceptibility testing was performed by disk diffusion agar testing. Biofilm formations were examined by glass tube assay and were incubated at 37°C under normoxia (21% oxygen) and hypoxia (1% oxygen). We observed that hypoxia affects the biofilm formation under hypoxic conditions as compared to normoxia. Among the antibiotics tested, penicillin, cephalosporin and carbapnem, all demonstrated decreased susceptibility values under hypoxia compared to normoxia. We established that hypoxia induced biofilm formation; this suggests that decreased oxygen may be a critical factor in the bacterial virulence. Moreover, we confirmed a strong positive correlation between hypoxia and antimicrobial resistance of P. aeruginosa.

There are many factors that affect the prescribing of a medication. Among them, promotion of a medication by the pharmaceutical companies, the physicians’ knowledge base, and pricing are the most important. The objective of this study was to demonstrate how these parameters affect the prescribing behavior and determine their affects on the prescription process. In order to investigate the effect of price, advertisement, and the physician gender and age on the sales and prescribing process of three medicines, namely fluvoxamine, clopidrogrel and latanoprosta the pooling data method in econometrics (Panel data) was used. We found that advertisement and medical insurance coverage for the medication had a significant positive effect on prescription of all three medicines. At the same time, a negative relationship was seen between increasing price and the frequency of prescription of a medicine. The gender and age of the physician also affected the behavior of prescribing. Moreover, we found out that advertisement has a direct effect on raising the demand and prescription of all the medicines. Health policy makers as well as pharmaceutical companies should consider the impact of advertisement and also the age and gender of the prescriber on the prescribing frequency of a particular medicine.

A simple, sensitive, selective and precise stability indicating HPLC method is developed and validated for the assay of ambrisentan in pharmaceutical dosage form. Separation of the drug was achieved on Agilent Zorbax C18 column (250 mm × 4.6 mm I.D., 5 μm particle size) under the isocratic mode of elution. The solvent system consisted of 0.1M potassium dihydrogen phosphate buffer (pH was adjusted to 4.4 with orthophosphoric acid) and methanol (30:70 v/v) at a flow rate of 1.0 ml/min. The method was carried out in the absorbance mode at 210 nm. The method was statistically validated according to International Conference on Harmonization guideline. Ambrisentan was subjected to stress degradation studies under acidic, basic, oxidative, thermal and photolytic conditions. The system was found to give compact peak for ambrisentan (Retention time is 3.315 min). The method was linear in the range of 1 - 150 µg/ml. The linear regression data for the calibration plot showed good relationship (r2 = 0.9996). The relative standard deviation and mean recovery values at different concentration levels were within limits. The performance of the method was not changed when small variations in the experimental conditions were made. Degradation products resulting from stress degradation studies did not interfere with the detection of ambrisentan. The proposed stability indicting HPLC method is simple, precise, accurate, robust and selective. This method can be used for quantification of ambrisentan in bulk drug and in pharmaceutical dosage forms.