Introduction

In our study we have used ocimum sanctum (Krishna Tulsi). It is commonly known as Tulsi in hindi and belongs to family Labiatae/Laminaceae. All parts of the plant are useful but leaves, seeds and roots are particularly of importance as medicinal agents. It is a hairy annual herb/undershrub of average height measuring 85 cms^1,2. The leaf of ocimum sanctum is elliptical. The leaf powder is green brown in colour and gives an aromatic smell like cloves³ .

The plant has been reported to possess various activities like antioxidant^4,5,6 antiasthmatic^7,8,9,10, antistress/adaptogenic¹¹, antipyretic and antiinflammatory¹², antiviral¹³, antibacterial¹⁴, insecticidal and antimalarial^15,16, antifungal¹⁴. Ocimum sanctum has also been investigated for its antiulcer activity^17,18,19,20. ^{Since studies regarding its antiulcer property are limited, we decide to evaluate its activity against stress induced gastric ulcers and compare the results with ranitidine as no comparison has been done in the previous studies.}

Materials and Methods

Animals

Drugs and Chemicals

Method for swimming stress induced gastric ulcers in rats

Statistical analysis

Observations and Results

Ulcers were induced in 100% animals in the distilled water (10ml/kg, orally) treated control group. In the dose of 50 mg/kg, orally, ocimum sanctum extract did not show protection from ulcers and though a decrease in the number of ulcers and the ulcer index was observed, it was not statistically significant. In the dose of 100 mg/kg, orally, ocimum sanctum extract showed protection from ulcers in 33.34% animals and also significantly (p<0.05) reduced the number of ulcers and the ulcer index. When administered in the dose of 200 mg/kg, orally, ocimum sanctum extract protected 50% animals from ulceration and also significantly (p<0.01 and p<0.05) reduced the number of ulcers and the ulcer index.

In the dose of 10 mg/kg, orally, ranitidine exhibited ulcer protection in 83.34% animals. It decreased the number of ulcers as well as the ulcer index significantly (p<0.001). (Table-1, Fig. 1 A & B).

Figure 1

: Effect of ocimum sanctum extract (OSE) on swimming stress induced gastric ulcers in albino rats

Figure 2

: Effect of ocimum sanctum extract (OSE) on swimming stress induced gastric ulcers in albino rats.

Figure 3

Discussion

The currently available antiulcer drugs either do not produce complete relief or cure or are associated with adverse effects and poor patient acceptability. Therefore, there is always the need to screen and develop better drugs for the treatment of peptic ulcer.

People all over the world are looking to various alternative systems of medicine especially herbal medicines which are non-toxic, claimed to be safe, cost effective and also equally effective in comparison to allopathic drugs.

Thus, with this idea, for our study we chose the medicinal plant ocimum sanctum for our study which has been reported to be safe and has been used for various medicinal purposes.

Psychological stress may be an important contributing factor in the causation of peptic ulcer^23,24. Stress has also been incriminated as either to cause or exacerbate peptic ulcer. Many stressful situations like burns, brain stem surgery, CNS tumours, trauma, stroke, sepsis, hypotension and even stressful life events may lead to gastric or duodenal ulcers²⁵.

Stress induced ulcers are probably mediated by histamine release with enhancement in acid secretion and a reduction in mucous production. Moreover, vagal overactivity has been suggested to be the principal factor in stress induced ulceration²⁶. Due to stress there is a breakdown in epithelial defense which appears to be due to decreased mucosal blood flow leading to ischemia, local acidosis, free radical formation and impaired rapid restitution. These effects allow back-diffusion of acid and cause further injury²⁷. The antiulcer activity of ocimum sanctum against swimming stress induced gastric ulcers in albino rats in the present study might be due to its histamine antagonistic, antisecretory and antioxidant effects. In one of our earlier studies, ocimum sanctum decreased plasma malondialdehyde (MDA) and increased serum superoxide dismutase (SOD) levels in which indicates it antioxidant activity²⁸.

Ocimum sanctum has shown significant ulcer protective effect as evident from the decrease in the percent incidence, number and severity of the ulcers in swimming stress induced gastric ulcers in albino rats. The antiulcer activity of ranitidine against stress ulcers is well known and is due to blockade of H₂ receptors. In this study, ranitidine was found to be more potent in comparison to ocimum sanctum.

It is therefore inferred that ocimum sanctum may be a useful antiulcer agent as shown by our experimental work. In view of its significant antiulcer activity which was comparable to ranitidine, more studies including human will be required to work out the complete potential of this plant in the prevention and treatment of peptic ulcer. Since earlier studies and this present work indicate a promising potential of the drug, it might be a useful agent in the management of peptic ulcer in future.