ethyl-cellulose and Hypertension

Continuous intravenous infusion of controlled drug delivery has certain risks. This could be diligently duplicated devoid of its hassles by using the skin as the port of drug entry. Transdermal drug delivery system is the main route with discrete, self-contained dosage forms when placed on the skin, transporting the medicament through the skin into the systemic circulation in a wellcontrolled manner.. The rationale of the current work was to formulate and evaluate a transdermal patch of an antihypertensive drug by using different grades of polymers with a view to circumvent the hepatic first pass metabolism and also to escalate its bioavailability.. Solvent-casting method was used to prepare transdermal patches of timolol maleate using Eudragit RL100, Eudragit RS100, ethyl cellulose as polymers, and dibutyl phthalate as the plasticizer. The formulated patches were evaluated for their physiochemical parameters such as folding endurance, percentage moisture content, thickness, and water vapour transmission. The formulated patches were subjected to in-vitro permeation studies by using a Franz diffusion cell with a dialysis sac. The optimized formulation chosen on the basis of physiochemical characteristics and in-vitro studies was subjected to in-vivo studies on methyl prednisolone acetate-induced hypertensive rats.. The data from release kinetics disclosed that the Korsmayer-Peppas could be the best fitting model. The results obtained from in-vitro studies disclosed that formulation with high proportion of Eudragit grade RL100 in acetone solvent system exhibited better drug release compared to rest of the formulations. The output obtained from in-vivo studies performed on rats revealed that the optimized formulation showed decrease in blood pressure from 158.53 ± 0.39 to 128.91 ± 0.50 mmHg.. It was concluded that timolol maleate patch could be formulated into a matrix-type transdermal patch for the management of hypertension.

Topics: Acrylic Resins; Administration, Cutaneous; Animals; Antihypertensive Agents; Cellulose; Drug Liberation; Hypertension; Male; Methylprednisolone; Methylprednisolone Acetate; Rats, Wistar; Timolol; Transdermal Patch

Captopril granules of controlled release with different polymers as ethylcellulose, ethyl/methylcellulose, and immediate release with polyvinylpyrrolidone (PVP) were developed by fluid bed dryer technique. The formulations were analyzed by scanning electron microscopy, X-ray powder diffraction, and dissolution profiles. To compare the formulations an in vivo setting rat blood pressure assay was performed, using angiotensin I as a vasoconstrictor agent. The scanning electron microscopy of granules showed differences in morphology, and X-ray powder diffraction technique presented some modification in crystalline structure of captopril in granules coated with PVP and ethyl/methylcellulose. The dissolution profile of granules coated with ethylcellulose showed a median time release of 4 hr whereas for granules coated with ethyl/methylcellulose, this time was 3.5 hr. The blockage of angiotensin I-induced hypertensive effect lasted 8 hr in granules coated with PVP and of more than 12 hr in the granules coated with ethylcellulose and ethyl/methylcellulose.

Topics: Administration, Oral; Angiotensin I; Angiotensin-Converting Enzyme Inhibitors; Animals; Antihypertensive Agents; Blood Pressure; Captopril; Cellulose; Chemistry, Pharmaceutical; Crystallography, X-Ray; Delayed-Action Preparations; Disease Models, Animal; Drug Compounding; Female; Hypertension; Kinetics; Methylcellulose; Microscopy, Electron, Scanning; Models, Chemical; Povidone; Powder Diffraction; Powders; Rats; Rats, Wistar; Solubility; Technology, Pharmaceutical

Hydroxypropylcellulose (HPC)-ethylcellulose (EC) microcapsules containing piretanide prepared by a solvent evaporation technique, were evaluated on pharmacokinetic, pharmacodynamic and pharmacological parameters in spontaneously hypertensive rats (SHR). HPC-EC10 (5:3) microcapsules showed sustained plasma piretanide levels and almost the same AUC (area under the curve) as compared with piretanide solution. Effect of treatment with the microcapsules (single oral administration per day in doses of 10 and 30 mg/kg) and the solution (double oral administration per day in doses of 5 and 15 mg/kg) was examined for 4 weeks on urine volume and urinary electrolytes excretion and blood pressure. The microcapsules and solution induced dose-dependent diuresis throughout the experimental period and a reduction in blood pressure from 2 weeks of the treatment. HPC-EC10 (5:3) microcapsules containing piretanide were satisfactory as a sustained-release preparation in the light of the anti hypertensive effect even at a half frequency of daily dosing of the solution.

Topics: Administration, Oral; Aldosterone; Animals; Blood Pressure; Body Weight; Cellulose; Diuretics; Drug Administration Schedule; Drug Compounding; Heart Rate; Hypertension; Male; Rats; Rats, Inbred SHR; Renin; Sulfonamides