Analgesic Activity Of Piper Nigrum Extract Per Se And Its Interaction With Diclofenac Sodium And Pentazocine In Albino Mice
S Pooja, R Agrawal, P Nyati, V Savita, P Phadnis
extract, tail flick latency, writhing
S Pooja, R Agrawal, P Nyati, V Savita, P Phadnis. Analgesic Activity Of Piper Nigrum Extract Per Se And Its Interaction With Diclofenac Sodium And Pentazocine In Albino Mice. The Internet Journal of Pharmacology. 2006 Volume 5 Number 1.
Black pepper is one of the oldest and best-known spices in the world. Belonged to Piperaceae family, which is cultivated in damp nutrient rich soil of South India, it is also found in Indonesia, Malaysia, and Brazil. In India it is called “
Its chief constituents are crystalline alkaloid piperine (5 -8.25 %), volatile oils (1-2.3 %) and a resin called Chavicin.1 Black pepper was found to enhance intestinal absorption of methionine and calcium ions.2
The present study was planned to investigate whether
Materials And Methods
The study was carried out on albino mice (20-30 g), maintained under standard laboratory conditions of food and water before start of the experiment. All experiments were carried out between 0900 and 1700 hr according to the guidelines for the care of laboratory animals.5 Animals were also kept under observation for 7 days, after the completion of experiment to observe acute or sub acute toxicity. The
All drugs were administrated orally half an hour before the onset of pain stimulus in different models of nociception in albino mice.
Vehicle 10 % v/v ethanol (10ml/kg), Diclofenac sodium (5mg/kg) in distilled water (DA), Diclofenac sodium in 10 % v/v ethanol (DB), Pentazocine (5mg/kg) in distilled water (PA), Pentazocine in 10 % v/v ethanol (PB), Test component
A factorial study design was planned. The animals were divided into four groups, of 8 animals each.
Group A control (vehicle treated) 10 % v/v ethanol, and Group C test component
For exploration of peripheral analgesic activity
Group B standard diclofenac sodium (solution DB),
Group D combination of diclofenac sodium (solution DA) and
For exploration of central analgesic activity
Group B standard pentazocine (solution PB),
Group D combination of pentazocine (solution PA) and
Determination of analgesic activity
Antinociceptive activity was assessed by two different models of nociception.
Abdominal constrictions were induced by 1 % v/v glacial acetic acid solution (10ml/kg, i.p.) 7 in mice pretreated with vehicle or one of the test substance. The number of abdominal writhing were measured over 20 min after the injection of acetic acid. Results were expressed as percentage inhibition of abdominal constrictions with respect to control.
The response was measured using the analgesiometer as described by the D'Armour and Smith.8 The tail flick latency was obtained thrice before drug administration, and mean was used as pre drug latency. The tail flick latencies were measured at 0, 0.50, 1, 2, and 4 h after the administration of vehicle or drug(s). A cut off time of 10 sec was planned to avoid any tissue damage in the animal.9 Results of tail flick latencies were expressed in terms of reaction time in seconds.
Group results are expressed as mean ± SEM. One – way ANOVA followed by Tukey's multiple comparison was applied for multiple comparisons amongst different groups.
Analgesic activity of individual drugs
(b) Diclofenac sodium
Diclofenac sodium at a dose of 5 mg/kg produced significant decrease in number of writhes (P<0.05).
In tail flick test, with a dose of 5 mg/kg of pentazocine, significant antinociceptive effect was observed 0.5 hr after the treatment, reaching peak at 2 h and the effect persisted for the entire test period (P<0.05).
Analgesic activity of Drug combinations
Diclofenac sodium in combination with
Pentazocine in combination with
No significant toxicity or mortality was observed during observation period of seven days after the completion of experiment.
Writhing and tail flick methods are the most common test for evaluating the analgesic efficacy of drugs/compound in rodents.
The abdominal constriction response induced by glacial acetic acid is a sensitive procedure to establish peripherally acting analgesics. This response is thought to involve local peritoneal receptors. The number of writhing observed during a 20 min period in control group was 51 ± 0.71 which correspond with the finding of other workers.
Tail flick method which is used for evaluating centrally acting analgesic effects of drugs showed no increase in latency when
A previous study done with nimesulide in albino mice shows a better therapeutic index and increased effect of nimesulide when co administered with Piperine.10
It is also claimed that piperine has some anti inflammatory activity 11 and anti convulsant activity 12.
Piperine has been reported to enhance the bioavailability of drugs like phenytoin, propanalol, rifampicin in humans.13, 14 This occurs as a result of a nonspecific and noncompetitive inhibitor of the metabolic enzymes.
The result of the present study showed that
In our experiment piperine is enhancing the activity of diclofenac and pentazocine the probable mechanisms of this enhancement may be:
Inhibition of metabolism: Piperine may inhibit different cytochrome P450 isoforms, UDP-glucuronyltransferase, hepatic arylhydrocarbon hydroxylase and other enzymes involved in drug and xenobiotic metabolisms. Piperine has also been found to inhibit CYP3A4 an enzyme important for the metabolism and transport of xenobiotics.15
Improvement in absorption: Piperine improving the absorption of drugs, perhaps by increasing GI blood flow 16 or by increasing permeability of intestinal cells by stimulating gamma-glutamyl transpeptidase activity and increased amino acid uptake.17 The absorption may also be enhanced due to its emulsifying action in the gut.18
Inhibition of efflux: Piperine also inhibits the efflux mechanism perhaps by inhibiting p- glycoprotein, the ‘pump' protein that removes substances from cells. This efflux inhibition promotes the stay of drug within the target cells for a longer period.19
Interference with solubilizer attachment: Some solubilizers such as glucuronic acid linked to the drug to enhance drug elimination. Piperine may inhibit this attachment as it has been shown to reduce the endogeneous UDP- glucuronic acid content of the cells.20
Further studies are needed to reveal the exact mechanism of action responsible for the enhanced activity of diclofenac sodium and pentazocine. However the study adds to our concept that piperine can enhance the activity of diclofenac and pentazocine. So the addition of piperine may reduce the required dose of these drugs that may help in reduction of their toxicity. Hence we recommend further studies to acknowledge their facts.
The author is grateful to Mr. N. Peter Amsar (P) LTD, Indore
Technical assistance of Dr. L. Lakhwani and Dr. G. Pawar is gratefully acknowledged.
The authors would also like to thank Drs. A. Jaiswal and S. Kuchya for their guidance and support.