Involvement of receptors in IDPH-791 induced prolongation of pentobarbitone hypnosis.

IDPH-791, when injected (ip) to mice potentiated the pentobarbitone sleeping time in a dose dependent manner. Involvement of neurotransmitters and receptors in this effect was studied using various receptor blockers, enzyme inhibitors, agonist and an amine depletor. Pretreatment with high dose of yohimbine (0.5 mg/kg), haloperidol, cyproheptadine, atropine and a combination of atropine and yohimbine significantly reversed the activity. Physostigmine, diethyldithiocarbamate and high dose of apomorphine (2.5 mg/kg) potentiated the subminimal effect of IDPH-791, whereas low dose of apomorphine (0.1 mg/kg) failed to potentiate. However, reserpine significantly reversed this response. Prazosin, phenoxybenzamine, low dose of yohimbine (0.25 mg/kg), propranolol, methysergide, mepyramine and cimetidine did not produce any change, thus ruling out the involvement of adrenergic, serotonergic and histaminergic systems. There seems to be simultaneous involvement of muscarinic receptors and postsynaptic dopamine (D2) receptors in IDPH-791 induced potentiation of pentobarbitone hypnosis.

Neuropsychopharmacological study of 2,4-dihydro[1,2,4]triazolo[3,4-c][1,4]benzothiazine-1-one (IDPH-791).

The neuropsychopharmacological profile of a new centrally acting skeletal muscle relaxant, 2,4-dihydro[1,2,4]triazolo[3,4-c][1,4]benzothiazine-1-one (IDPH-791), an analogue of triazolobenzothiazine, has been described and compared to mephenesin, a well known centrally-acting muscle relaxant. IDPH-791 was found to be safer and of longer duration of action than mephenesin in all the tests conducted in this study. Both IDPH-791 and mephenesin caused ataxia, decrease in spontaneous activity and inhibition of pinnal reflex. IDPH-791 was 1.5 to 2.0 times more potent in exhibiting motor inco-ordination and anticonvulsant activity than mephenesin in mice and rats. IDPH-791 was twice as active in inhibiting various spinal polysynaptic reflexes, crossed extensor, flexor, and linguomandibular reflexes; however, both did not affect the typical monosynaptic reflex, patellar reflex. IDPH-791 and mephenesin did not have sedative activity. Although mephenesin exhibited haemolytic activity, IDPH-791 was devoid of this activity. It is concluded that IDPH-791 is a safe and effective centrally-acting muscle relaxant having a longer duration of action than mephenesin. IDPH-791 is also devoid of sedative and haemolytic activity.

Efficacy of potassium and magnesium in essential hypertension: a double-blind, placebo controlled, crossover study.

OBJECTIVE: To evaluate the antihypertensive activity of potassium given alone or in combination with magnesium in patients with mild hypertension. DESIGN: A double blind, randomised, placebo controlled, crossover trial of 32 weeks' duration. SETTINGS: Cardiology outpatient department, Sassoon General Hospitals, Pune, India. PATIENTS: 37 Adults with mild hypertension (diastolic blood pressure less than 110 mm Hg). INTERVENTION: Patients received either placebo or potassium 60 mmol/day alone or in combination with magnesium 20 mmol/day in a crossover design. No other drug treatment was allowed. MEASUREMENTS: Blood pressure and heart rate assessed at weekly intervals and biochemical parameters at monthly intervals. RESULTS: Potassium alone or in combination with magnesium produced a significant reduction in systolic and diastolic blood pressures (p less than 0.001) and a significant reduction in serum cholesterol concentration (p less than 0.05); other biochemical variables did not change. Magnesium did not have an additional effect. Urinary potassium excretion increased significantly in the groups who received potassium alone or in combination with magnesium. The drug was well tolerated and compliance was satisfactory. CONCLUSION: Potassium 60 mmol/day lowers arterial blood pressure in patients with mild hypertension. Giving magnesium as well has no added advantage.

Effect of 'Arogyavardhini' against carbon tetrachloride induced hepatic damage in albino rats.

'Arogyavardhini'-an indigenous formulation was evaluated for its hepatoprotective activity in rats, using two models of carbon tetrachloride (CCl4) hepatic damage, one simulating vital hepatitis and the other simulating fatty change. The protective effect was assessed from serum aspartate transaminase (AST) and alkaline phosphatase levels and from histopathological changes in liver. The results revealed that 'Arogyavardhini' (5 mg/100g, PO daily) was effective in minimizing the changes in serum levels of AST and alkaline phosphatase induced by CCI. The protective effect was also evident on histopathological examination.

Effects of enfenamic acid on renal electrolyte excretion in hypertensive patients.

Single and multiple doses of enfenamic acid were compared in hypertensive patients with those of hydrochlorothiazide using urinary output and electrolytes as parameters. With enfenamic acid, excretion of Na+, K+, and Cl- was significantly decreased in the multiple-dose study; after single doses, there was a significant decrease in the excretion of Na+ and Cl- only.