Inhibitory effect of Careya arborea on inflammatory biomarkers in carrageenan-induced inflammation.

CONTEXT: Careya arborea Roxb. (Lecythidaceae) has multiple applications in traditional medicine; it exhibits analgesic, antibacterial, anti-inflammatory, antiulcer, and protective effects. However, the effect of C. arborea on biochemical and immmunological inflammatory mediators has not been explored. OBJECTIVE: The present study investigates the anti-inflammatory potential of the methanol extract of C. arborea stem bark and further assesses its possible mechanism on the modulation of inflammatory biomarkers. MATERIALS AND METHODS: Anti-inflammatory activity of C. arborea methanol extract (CAME) was evaluated (100 and 200 mg/kg, p.o) using indomethacin (10 mg/kg, p.o) as the standard drug in Wistar albino rats. Inflammation was induced by injecting 0.1 ml carrageenan (1% w/v) into the left hind paw. The anti-inflammatory mechanism was studied by measuring malondialdehyde (MDA), C-reactive protein (CRP), nitric oxide (NO), myeloperoxidase (MPO), TNF-α, and IL-1ß levels in both control and treated groups. A protocol has also been established to quantify quercetin and betulinic acid content in CAME using HPTLC fingerprint. RESULTS: Careya arborea significantly (p < 0.001) decreased carrageenan-induced paw edema, showed a reduction of 48.87 and 65.53% at doses of 100 and 200 mg/kg, respectively. Moreover, CAME significantly decreased the MDA, CRP, NO, and MPO levels, elevated by carrageenan induced inflammation. CAME also markedly down-regulated serum TNF-α and IL-1ß levels. These findings were further supported by the histological study. The content of quercetin and betulinic acid in CAME was found to be 0.177 and 3.14%, respectively. CONCLUSION: Several mechanisms, including the inhibition of pro-inflammatory cytokines, enzymes and mediators release, appear to account for the anti-inflammatory potential of C. arborea.

Thiazolidine-2,4-diones derivatives as PPAR-γ agonists: synthesis, molecular docking, in vitro and in vivo antidiabetic activity with hepatotoxicity risk evaluation and effect on PPAR-γ gene expression.

A library of conjugates of chromones and 2,4-thiazolidinedione has been synthesized by Knoevenagel condensation followed by reduction using hydrogen gas and Pd/C as a catalyst. Compounds 5c and 5e were most effective in lowering the blood glucose level comparable to standard drug pioglitazone. Compound 5e exhibited potent PPAR-γ transactivation of 48.72% in comparison to pioglitazone (62.48%). All the molecules showed good glide score against the PPAR-γ target in molecular docking study. PPAR-γ gene expression was significantly increased by compound 5e (2.56-fold) in comparison to standard drug pioglitazone. Compounds 5e and 5c did not cause any damage to the liver and may be considered as promising candidates for the development of new antidiabetic agents.

Effect of rosuvastatin on obesity-induced cardiac oxidative stress in Wistar rats--a preliminary study.

The prevalence of obesity has been rising alarmingly and it has now become a global concern causing an enormous economic burden on the health care system. Obesity is generally linked to complications in lipid metabolism and oxidative stress. The aim of the present study was to investigate the effect of rosuvastatin (10 mg/kg, po) on obesity-induced oxidative stress in high fat-fed Wistar rats. Oral administration of rosuvastatin (10 mg/kg) for 21 days along with high fat diet brought about significant elevation in serum high density lipoprotein and cardiac antioxidant enzymes levels (superoxide dismutase, catalase, glutathione, glutathione peroxidase, glutathione peroxidase-, glutathione reductase- and glutathione-S-transferase) while decreasing in serum lactate dehydrogenase, apolipoprotein-B, lipids (triglycerides, total cholesterol, low density lipoprotein-cholesterol, very low density lipoprotein-cholesterol and atherogenic index) and cardiac thiobarbituric acid reactive substances levels. The results were comparable with orlistat, a standard antiobesity drug. These preliminary results for the first time demonstrate that administration of rosuvastatin can be beneficial for the suppression of obesity-induced oxidative stress and dyslipidemia in high fat-fed Wistar rats.

Enhancement of antioxidant defense mechanism by pitavastatin and rosuvastatin on obesity-induced oxidative stress in Wistar rats.

CONTEXT: There has been a steady increase in the epidemiology of obesity over the last 30 years with developed countries leading the way. Oxidative stress was believed to be the principle contributor to the development of cardiovascular disorders that linked with obesity. OBJECTIVE: To evaluate the enhancement of antioxidant defense mechanism by Pitavastatin (PTV) and Rosuvastatin (RSV) on obesity-induced oxidative stress in Wistar rats. METHODS: Fifty Wistar albino rats were divided into five groups. High fat diet (HFD, 20 g/day/rat) pellets were given for 28 days to produce obesity-induced oxidative stress in Wistar rats. Oral administration of HFD along with PTV, RSV and Orlistat [(HFD for 28 days + from 8th day PTV (1 mg/kg), RSV (5 mg/kg) and Orlistat (10 mg/kg) to 28th day] were given respectively. RESULTS: Both PTV and RSV produced significant (p < 0.01) reduction in serum apolipoprotein-B (Apo-B), total cholesterol (TC), triglycerides (TGs), cardiac-lipid peroxides (TBARS) levels and elevation in serum high density lipoprotein (HDL-C), cardiac antioxidant enzymes [glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), superoxide dismutase (SOD) and catase (CAT)] levels. DISCUSSION AND CONCLUSION: Results were comparable with Orlistat, a standard antiobesity drug and present initial evidence that Pitavastatin and Rosuvastatin are useful for the treatment of obesity by enhancing the antioxidant defense mechanism. However, the effects of PTV were more prominent than RSV. The present findings of Pitavastatin and Rosuvastatin raise the possibility of a new application as an antiobesity therapeutic modality.

Pharmacokinetic-pharmacodynamic equivalence of three gliclazide formulations in healthy human male subjects.

AIMS: To find out the pharmacokinetic (PK) and pharmacodynamic (PD) parameters for assessing the bioequivalence of three marketed products. To study the relationship between the pharmacokinetics of gliclazide and pharmacodynamic effect in healthy male volunteers. METHODS: This was an open label, balanced, randomized, 3-treatment, 3-sequence, 3 period, single-dose, cross-over bioavailability study in which 18 healthy adults were randomized to receive gliclazide 80 mg with 7 days wash out between treatments. The drug was administered with 240 ml of 20% glucose solution after a 10 h overnight fasting. Pharmacokinetic parameters like t(max), C(max), AUC(0-t), AUC(0-∞), AUC(0-t) / AUC(0-∞) and t(1/2) and pharmacodynamic parameters like maximum effect (minimum glucose level in the body, C(minglu)), time to minimum glucose level in the body (T(cminglu)) and partial AUC were calculated for all the products. RESULTS: The values for mean ± SD for age, height and weight of the volunteers were 28.00 ± 22.68, 165.78 ± 5.56 and 56.78 ± 13.37 respectively. There were total 4 withdrawn subjects and 1 drop out. Within batch accuracy of the method were in the range of 95.5 - 101.7%, 99.1 - 106.1% and 96.2 - 104.2% for three consecutive batches. The 90% CI for log transformed data of the PK and PD were within the acceptance range of 80.0 - 125.0%. CONCLUSIONS: This population PKPD analysis has characterized the relationship between the exposure to gliclazide and its hypoglycemic effect. The test products A & B compared to reference product R were bioequivalent on the basis of pharmacokinetic and pharmacodynamic parameters. Finally it is recommended that the more costly product R can be safely switched with less costly products i.e. A and B.

Effect of aloe vera (Aloe barbadensis Miller) gel on doxorubicin-induced myocardial oxidative stress and calcium overload in albino rats.

Administration of a single dose of doxorubicin (DOX) (7.5 mg/kg, i.v.) produces cardiotoxicity, manifested biochemically by significant decrease in blood glutathione (GSH) and tissue GSH along with elevated levels of serum lactate dehydrogenase (LDH) and serum creatine phosphokinase (CPK). In addition, cardiotoxicity was further confirmed by significant increase in lipid peroxides expressed as malondialdehyde (MDA, secondary indicator of lipid peroxidation), tissue catalase and tissue superoxide dismutase (SOD). Administration ofA. vera gel (100 and 200 mg/kg) orally for 10 days produced a significant protection against cardiotoxicity induced by DOX evidenced by significant reductions in serum LDH, serum CPK, cardiac lipid peroxides, tissue catalase and tissue SOD along with increased levels of blood and tissue GSH. The results revealed that A. vera gel produced a dose dependent protection against DOX induced cardiotoxiaty.

Drug utilization of oral hypoglycemic agents in a university teaching hospital in India.

BACKGROUND: India has witnessed a rapidly exploding epidemic of diabetes in recent years and currently leads the world with the largest number of diabetic subjects in a single country. World Health Organization estimates that in 2000, 31.7 million individuals were affected by diabetes in India and these numbers will rise to 79.4 millions by the year 2030. In view of the above situation, drug utilization review of antidiabetic medicines in Indian healthcare settings has a valid significance to promote rational drug use in diabetics. OBJECTIVE: The present study is aimed to determine the drug utilization patterns in type 2 diabetic patients on oral hypoglycemic agents in the Medicine Outpatient Department (OPD) and Inpatient Department (IPD) of Majeedia Hospital, a teaching hospital of Hamdard University, New Delhi. METHODS: Patients with established type 2 diabetes (n = 218) visiting the OPD and IPD were interviewed using a structured questionnaire during the period January-May 2006. RESULTS: A majority of the type 2 diabetic patients in this setting were treated with multiple antidiabetic drug therapy. The most commonly prescribed antidiabetic drug class was biguanides (metformin) followed by sulphonylureas (glimepiride), thiazolidinediones (pioglitazone), insulin and alpha-glucosidase inhibitors (miglitol). As monotherapy insulin was the most common choice followed by metformin. The most prevalent multiple therapy was a three-drug combination of glimepiride + metformin + pioglitazone. More than half of the type 2 diabetic patients showed poor adherence (compliance) to the prescribed therapy. CONCLUSION: This study strongly highlights the need for patient education or counselling on use of antidiabetic and concomitant drugs, monitoring of blood glucose and glycosylated haemoglobin (HbA1c) levels, diet control, and correction of diabetic complications. Metabolic control was poor and HbA1c monitoring was underutilized. Clinical monitoring of patients' adherence to prescribed treatments is recommended and measures should be taken to improve it.

Effect of combined treatment of thioperamide with some antiepileptic drugs on methionine-sulfoximine induced convulsions in mice.

Methionine-sulfoximine (MSO), a convulsant is known to increase the activity of histamine N-methyl transferase. The effect of a selective H3 receptor agonist R- (alpha) methylhistamine (RAMH) and antagonist (thioperamide, THP) and some antiepileptic drugs (gabapentin and sodium valproate) have been evaluated on MSO-induced convulsions in mice. The effect of THP was also evaluated in combination with these antiepileptic drugs. Sodium valproate (300 mg/kg, po) and gabapentin (400 mg/kg, po) offered protection against MSO-induced convulsions as evidenced by a significant prolongation of latency to abnormal dorsoflexion and complete protection against mortality within 6 h of administration. THP (15 mg/kg, ip) alone and in combination with sub-effective doses of gabapentin (75 mg/kg, po) and sodium valproate (75 mg/kg, po) revealed no significant differences from the control group or either drug alone. Hence, the convulsant action of MSO does not appear to be mediated via histaminergic mechanisms.

The effects of rosuvastatin on the serum cortisol, serum lipid, and serum mevalonic acid levels in the healthy Indian male population.

In this open-label, balanced, randomized, placebo-controlled, parallel study, healthy male volunteers were randomly divided into two groups. Each group received either a single oral dose of rosuvastatin 20 mg or placebo. Estimations were done at predose on day 1 of dosing (baseline) and 24 h postdose after days 7 and 14. Serum cortisol and serum lipid levels were estimated using enzyme-linked immunosorbent assay kits and serum mevalonic acid (MVA) levels were measured using validated liquid chromatography-tandem mass spectrometry method. Rosuvastatin produced a statistically significant (P < 0.05) decrease in total cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and triglycerides. However, the increase in high-density lipoprotein cholesterol and decrease in cortisol and MVA were not statistically significant when compared to the placebo-treated group. The study showed that rosuvastatin at a dose of 20 mg/day for a period of 14 days was very potent as cholesterol-lowering agent, without any significant change in serum cortisol level in the healthy Indian male population.

Hepatoprotective and behavioral effects of jigrine in galactosamine-induced hepatopathy in rats.

The hepatoprotective activity of jigrine, a polypharmaceutical herbal formulation, at a dose of 1 mL/kg/day p.o. was evaluated against galactosamine (400 mg/kg b.wt.)-induced hepatopathy in rats. Biochemical parameters such as alanine trasaminase (ALT), alkaline phosphatase (ALP), and bilirubin were estimated to assess liver function. Jigrine was also evaluated for its effect on the possible behavioral alterations secondary to liver damage produced by galactosamine (d-Gal) administration in rats. The d-Gal-induced elevation in serum levels of ALT, ALP, and bilirubin was significantly reduced (p values <0.01, <0.01, and <0.05, respectively) in jigrine- and silymarin-pretreated rats. Jigrine pretreatment also exhibited beneficial effects on d-Gal-induced behavioral abnormalities in rats. Silymarin (25 mg/kg/day p.o.) was used as reference standard. The biochemical observations were supplemented with histopathological examination of rat liver sections. Histopathological evaluation showed marked improvement in the livers of jigrine- and silymarin-treated animals.

Synthesis and antiinflammatory activity of some new 1,3,5-trisubstituted pyrazolines bearing benzene sulfonamide.

Nineteen new 2-pyrazoline bearing benzenesulfonamide derivatives were synthesized by condensing chalcones with 4-hydrazinonbenzenesulfonamide hydrochloride. Their chemical structures were proved by means of IR, (1)H NMR, (13)C NMR, mass spectroscopic and elemental analyses data. These compounds were tested at dose of 20mg/kg for their anti-inflammatory activity in carrageenan-induced rat paw edema model and volume of paw edema was measured at 0, 3 and 5h. Two compounds 3k and 3l were found to be more active than celecoxib throughout the study (at 3 and 5h). While two other compounds 3m and 3n showed more potent activity than celecoxib at 5h. They are devoid of ulcerogenic potential when administered orally at a dose of 60 mg/kg. Compounds (3k-m) showed COX-1 and COX-2 inhibitory activity at 0.05 microM.

Serotonergic mechanisms in the 6-Hz psychomotor seizures in mice.

Serotonin (5-hydroxytrytamine (5-HT)) plays an important role in experimental seizures. Recently, we reported the depletion of 5-HT by parachlorophynylalanine (PCPA) in whole brain to enhance 6-Hz psychomotor seizures in mice. In the present work, we investigated the effect of 5-HT depletion in cortex and hippocampus, brain regions relevant for epilepsy, on behavioral and ultra-structural changes following 6-Hz psychomotor seizures in mice. In addition, we studied the effect of sodium valproate (SVP) on behavioral, biochemical, and ultra-structural effects induced by 6 Hz. Behavioral changes induced by 6 Hz stimulation were characterized as the increased duration of Straub's tail, stun position, twitching of vibrissae, forelimb clonus, and increased rearing and grooming. PCPA administration further enhanced while SVP reduced these behaviors in mice. The 6-Hz psychomotor seizure induced ultra-structural changes in both cortex and hippocampus in mice treated with PCPA. Furthermore, PCPA administrations followed by 6Hz-induced seizures were accompanied by reduced hippocampal and cortical 5-HT. SVP attenuated the PCPA-induced ultra-structural changes and alterations of 5-HT content in the mouse brain. The study suggests the involvement of 5-HT in the 6 Hz psychomotor seizures and in the mechanisms of action of SVP against such seizures in mice.

Influence of grape juice and orange juice on the pharmacokinetics and pharmacodynamics of diltiazem in healthy human male subjects.

OBJECTIVE: The objective was to study the effect of grape juice and orange juice on the pharmacokinetics (PK) and pharmacodynamics (PD) of diltiazem in healthy human volunteers. METHODOLOGY: The study design was open-label, balanced, randomized, 3-period, single-dose and crossover. A group of 12 healthy, adult, male human volunteers received a single oral dose of diltiazem 180 mg extended release capsule on three different occasions: with 200 ml of water, with 200 ml of grape juice and with 200 ml of orange juice in random order. A washout period of 7 days was kept between each study period. Serial blood samples were collected up to 24 h post dose and assayed for diltiazem using a specific and validated HPLC method. Blood pressure (BP) and ECG measurements were done at 0, 1, 2, 3, 4, 6, 8, 10, 12, 16 and 24 h post dose. Analysis of variance was carried out using logarithmic transformations of AUC and Cmax as well as nontransformed tmax. RESULTS: No significant change was observed in heart rate and BP. The median tmax was identical in all three occasions. The 90% CI of the Cmax ratios for orange juice/water were 104.59 - 114.86 and for grape juice/water were 93.91 - 103.13. Similarly, the 90% CI of the AUC0-inf ratios for orange juice and grape juice vs. water were 103.68 - 119.83 and 88.56 - 104.06, respectively. Since these values fall within the bioequivalence criteria of 80 - 120% limits, our study demonstrates absence of interaction of diltiazem with grape juice or orange juice. CONCLUSIONS: There is no significant influence of grape juice or orange juice on the pharmacokinetics and pharmacodynamics of diltiazem.

Beneficial effect of Embelia ribes ethanolic extract on blood pressure and glycosylated hemoglobin in streptozotocin-induced diabetes in rats.

Embelia ribes (common name, Vidanga) is extensively used in traditional system of medicine for treatment of various disorders. It is described in Ayurveda, as a powerful anthelmintic, antifertility and antihyperlipidemic agent. The present study was undertaken to investigate modulatory effect of 6 weeks' chronic oral administration of E. ribes ethanolic extract on diabetes mellitus induced by a diabetogen, streptozotocin (STZ) with special reference to changes in glucose levels, glycated haemoglobin status and cardiac toxicity. STZ treatment (40 mg/kg iv) resulted in significant increase in blood glucose levels, glycated haemoglobin levels, heart rate (HR) and systolic blood pressure (SBP). Oral administration of E. ribes ethanolic extract in dose of 100 mg/kg and 200 mg/kg significantly reduced the levels of blood glucose, glycated haemoglobin, heart rate (HR) and systolic blood pressure (SBP) in animals when compared with diabetic rats.

Thioperamide reduces intracellular calcium in mouse brain synaptosomes.

Intracellular calcium regulation is vital for cells, especially for neurons; raised levels are associated with cytotoxicity and neuronal death. In this report, we present the first experimental evidence showing a concentration-dependent reduction of free calcium in the mouse brain synaptosomes by thioperamide (THP), an H3 receptor antagonist. This is interesting in view of the recent reports on the anticonvulsant and cognition facilitating effects of THP. A neuroprotective potential of THP is suggested.

Protective effect of bezafibrate on streptozotocin-induced oxidative stress and toxicity in rats.

The present study was aimed to find out the protective effect of bezafibrate on lipid peroxidation (LPO), activities of both enzymatic and non-enzymatic antioxidants and histopathological examination of pancreas in streptozotocin (STZ)-induced diabetic rats. Experimental diabetes was induced by a single dose of STZ (60mg/kg, i.p.) injection. The oxidative stress was measured by tissue LPO level, reduced glutathione (GSH) content and by enzymatic activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) in liver and pancreas. Biochemical observations were further substantiated with histological examination of pancreas. The increase in blood glucose, LPO level with reduction in GSH content and decreased enzymatic activities were the salient features observed in diabetic control rats. Administration of bezafibrate (30mg/kg day, p.o.) for 15 days caused a significant reduction in blood glucose and LPO level in STZ treated rats (group III) when compared with diabetic control rats (group II). Furthermore, bezafibrate treated diabetic rats (group III) showed significant increase in the activities of both enzymatic and non-enzymatic antioxidants when compared to diabetic control rats (group II). Degenerative changes of pancreatic beta-cells in STZ treated rats were minimized to near normal morphology by administration of bezafibrate as evident by histopathological examination. The results obtained clearly indicate the role of oxidative stress in the induction of diabetes and suggest a protective effect of bezafibrate in this animal model.

Effect of chronic chromium picolinate in animal models of anxiety and memory.

Diabetes mellitus is associated with certain neurological problems such as depression, anxiety, memory impairment, etc. As chromium picolinate (CrP), a widely used trace element is shown to have beneficial effects in diabetes and depression, we investigated its effects on elevated plus maze and spontaneous alternation behavior paradigm as a measure of anxiety and memory, respectively. CrP (8 microg/mL in drinking water) significantly increased percentage preference to open arm in elevated plus maze in diabetic and normal rats. However, no significant changes were observed in percentage alternation after CrP chronic treatment. The possible anxiolytic effect of CrP might be related to its effect on serotonergic transmission.

Protective role of curcumin in myocardial oxidative damage induced by isoproterenol in rats.

This study was designed to investigate the effect of oral curcumin pretreatment (200 mg/kg) on isoproterenol-induced myocardial injury in rats. Isoproterenol (85 mg/kg, s.c., in two divided doses at 24 h intervals) administration induced a statistically significant increase (P < 0.01) in serum lactate dehydrogenase, creatine kinase, aspartate transaminase, and alanine transaminase activities and significant increase (P < 0.01) in myocardial lipid peroxides levels as compared to vehicle control rats. Furthermore, significant depletion (P < 0.01) of myocardial endogenous antioxidants viz. superoxide dismutase, catalase, and tissue glutathione levels were also found in the pathogenic control group, that is, isoproterenol only treated animals. Curcumin (200 mg/kg) pretreatment for 20 days in isoproterenol treated rats significantly lowered (P < 0.01) the serum lactate dehydrogenase, creatine kinase, aspartate transaminase, alanine transaminase, and myocardial lipid peroxides levels and increased the levels of myocardial endogenous antioxidants (superoxide dismutase, catalase, and tissue glutathione) as compared to pathogenic control rats. Furthermore, histological examination of rat's heart section confirmed myocardial injury with isoproterenol administration and near normal pattern with curcumin pretreatment. The results of our study provide clear evidence that the curcumin pretreatment enhances the antioxidant defense against isoproterenol-induced oxidative myocardial injury in rats and exhibit cardioprotective property.

Antipsychotic-like profile of thioperamide, a selective H3-receptor antagonist in mice.

Experimental and clinical evidence points to a role of central histaminergic system in the pathogenesis of schizophrenia. The present study was designed to study the effect of histamine H(3)-receptor ligands on neuroleptic-induced catalepsy, apomorphine-induced climbing behavior and amphetamine-induced locomotor activities in mice. Catalepsy was induced by haloperidol (2 mg/kg p.o.), while apomorphine (1.5 mg/kg s.c.) and amphetamine (2 mg/kg s.c.) were used for studying climbing behavior and locomotor activities, respectively. (R)-alpha-methylhistamine (RAMH) (5 microg i.c.v.) and thioperamide (THP) (15 mg/kg i.p.), per se did not cause catalepsy. Administration of THP (3.75, 7.5 and 15 mg/kg i.p.) 1 h prior to haloperidol resulted in a dose-dependent increase in the catalepsy times (P < 0.05). However, pretreatment with RAMH significantly reversed such an effect of THP (15 mg/kg i.p.). RAMH per se showed significant reduction in locomotor time, distance traveled and average speed but THP (15 mg/kg i.p.) per se had no effect on these parameters. On amphetamine-induced hyperactivity, THP (3.75 and 7.5 mg/kg i.p.) reduced locomotor time, distance traveled and average speed (P < 0.05). Pretreatment with RAMH (5 microg i.c.v.) could partially reverse such effects of THP (3.75 mg/kg i.p.). Climbing behavior induced by apomorphine was reduced in animals treated with THP. Such an effect was, however, reversed in presence of RAMH. THP exhibited an antipsychotic-like profile by potentiating haloperidol-induced catalepsy, reducing amphetamine-induced hyperactivity and reducing apomorphine-induced climbing in mice. Such effects of THP were reversed by RAMH indicating the involvement of histamine H(3)-receptors. Findings suggest a potential for H(3)-receptor antagonists in improving the refractory cases of schizophrenia.

Effect of chromium picolinate on modified forced swimming test in diabetic rats: involvement of serotonergic pathways and potassium channels.

Depression occurs frequently in patients with diabetes mellitus. Chromium picolinate, an essential trace element is recommended for diabetes and also has been reported to benefit depression, but its mechanism is still debated. To investigate the mechanism, we studied its effects on serum insulin, serum glucose and on modified forced swimming test, a behavioural paradigm for depression in rats. The study involving co-administration of sub-active doses of glimepiride, a K(+) channel blocker and chromium picolinate on blood glucose levels and modified forced swimming test was also performed to probe any role of K(+) channels in its antidiabetic and antidepressants effects. Streptozotocin (55 mg/kg, intraperitoneally) was injected in rats to induce diabetes (Type 1). After a week, chromium picolinate (8 microg/ml in drinking water) was administered for 4 weeks. Normal rats received similar drug treatment. The sub-active doses of chromium picolinate (4 microg/ml in drinking water) and glimeperide (2.5 mg/kg, orally) were co-administered and their effects on modified forced swimming test and on glucose levels were measured. Chromium picolinate (8 microg/ml in drinking water) produced hypoglycaemia in diabetic and normal rats. It had no effects on the streptozotocin-induced reduction in insulin levels. Chromium picolinate (8 microg/ml in drinking water) increased swimming with subsequent decrease in immobility. The sub-active doses of chromium picolinate and glimeperide showed significant additive effects in modified forced swimming test and reduction in serum glucose concentrations, though statistically insignificant. In conclusion chromium picolinate shows antidepressant action on modified forced swimming test affecting only swimming that suggests serotonergic pathways involvement. The additive effects on swimming in modified forced swimming test and reduction in serum glucose levels shows involvement of K(+) channels in antidiabetic and antidepressant actions of chromium picolinate.