|Year : 1985 | Volume
| Issue : 5 | Page : 313-315
Evaluation of effects of clofibrate, an antilipaemic agent on intraocular pressure in experimental glaucoma
MC Gupta, P Khosla, KN Garg
Department of Pharmacology, Medical College, Rohtak, India
18/8 FM, Medical Enclave Medical College, Rohtak (Haryana)
|How to cite this article:|
Gupta M C, Khosla P, Garg K N. Evaluation of effects of clofibrate, an antilipaemic agent on intraocular pressure in experimental glaucoma. Indian J Ophthalmol 1985;33:313-5
|How to cite this URL:|
Gupta M C, Khosla P, Garg K N. Evaluation of effects of clofibrate, an antilipaemic agent on intraocular pressure in experimental glaucoma. Indian J Ophthalmol [serial online] 1985 [cited 2013 May 24];33:313-5. Available from: http://www.ijo.in/text.asp?1985/33/5/313/30738
In the origin of acute glaucoma attack the neurovascular circulation plays an important role. In other vascular crises an elevation of blood lipid concentration is generally known. Higher concentrations of free fatty acids were found during acute attack of glaucoma which were lowered after the passage of the emergency.
In the vascular crises there is an increased viscosity of blood and the serum lipid content is higher. Shafrir also found increased concentration of nonesterified fatty acids in cases of glaucoma. Miller studied fasting plasma lipoprotein levels and showed an elevation of plasma cholesterol in low tension glaucoma.
Dienstbier showed that serum lipoprotein contents of glaucoma patients agree with those of arteriosclerotic patients.
Clofibrate, an antilipaemic agent, was introduced for the reduction of serum cholesterol and serum triglycerides levels in patients with ischaemic heart disease. It reduces serum lipids and interferes with blocd clotting.
The idea of using clofibrate in glaucoma patients seems to have arisen from investigations by Hanisch of the blood chemistry during attacks of acute congestive glaucoma, which suggested an increase in the concentration of unesterified fatty acids.
Orban used clofibrate in the treatment of acute closed angle glaucoma and it was claimed that single dose of clofibrate relieved the attack in eight out of ten cases, Cullen tried effect of clofibrate in patients with chronic simple and secondary glaucoma, who had not responded to other treatment and in whom operation was envisaged. In half of the patients intra-ocular pressure fell significantly.
Gloster studied effects of clofibrate on the intraocular pressure in rabbits. No significant difference was found in the level of tension between treated and untreated animals. Ramsell and Roth in a trial of clofibrate treatment of chronic simple glaucoma found no significant difference in intraocular pressure before and after treatment
In the present study, experimental glaucoma was produced in rabbits to evaluate the effects of clofibrate, an antilipaemic agent, on the intra-ocular pressure.
| Material and methods|| |
This study was carried out in a group of thirty albino rabbits of both sexes and weighing from 1.5-2.0 kg. These were kept on a controlled standard diet. Water was provided ad. lib. These were further divided into three sub groups of ten animals each.
Sub-group I; control; No drug was given. Glaucoma was produced in one eye the other eye serving as control.
Sub-group II: In this subgroup of animals clofibrate was given before producing glaucoma in daily dose of 625 mg I/M for four days. On the fifth day glaucoma was produced.
Sub-group III : In these animals clofibrate was given 625 mg I/M after producing Glaucoma.
Intra ocular pressure was recorded in both the eyes with the help of Schiotz's tonometer, before producing glaucoma and after producing glaucoma for three hours, at one hour interval and then on second and third day. Antibiotic drops were put into both the eyes so as to prevent any possibility of infection.
| Observations|| |
Sub-group I :
In these animals a marked rise in intraocular pressure occurred. It started rising within an hour and reached the peak levels by third hour. Average normal intraocular pressure of 23.0±0.54 mm of Hg increased to 47.3±1.96 mm of Hg in 3rd hour (P<0.001) [Figure - 1]. Intraocular pressure started declining by second day and returned almost to normal levels by third day. There was marked congestion along with dilatation of the pupil. There was also oedema and haziness of cornea.
Sub-group II :
In these animals there was a rise in intraocular pressure but the values were much less as compared to the values in subgroup I. Average intraocular pressure was only 37.8±0.91 mm of Hg in the third hour as compared to 47.3±1.96 mm of Hg in subgroup I (p<0.01).
Sub-group III :
In this subgroup in which treatment with clofibrate was given after producing glaucoma, the mean value of intraocular pressure was only 34.8±0.96 mm of Hg in the third hour as compared to a value of 47.3±1.96 mm of Hg in the untreated animals (p<0.01). There was a rise in intraocular pressure after injecting 20% liquid paraffin into the anterior chamber. But there was no further rise following injection of clofibrate.
| Discussion|| |
On the basis of the biochemical changes occurring in the blood, it has been hypothesized that if in acute cases of glaucoma, the concentration of various lipid fractions and thereby viscosity of blood could be brought down by administration of certain drugs, then the intraocular pressure also must become lowered. If in cases of glaucoma, lipid concentration is brought down or normalised by clofibrate, then the manifestations of glaucoma attack should also cease. In the present study clofibrate by its antilipaemic action has been used for this purpose.
Clofibrate could be used in glaucoma patients also, was revealed by Hanisch wh demonstrated an increased concentration of free fatty acids and other lipids during glaucoma attack. Many other workers used clofibrate in glaucoma patients and found it to be effective in the cases where there was no response to other drugs,,,.
In other studies, however, it was reported that clofibrate did not have any significant use in patients with glaucoma or in certain animal studies,.
In our study clofibrate was given both before and after producing glaucoma in rabbits. This was done so as to find out any effect of cloribrate to prevent glaucoma attack or its usefulness as a treatment.
In the animals where it was given prior to producing glaucoma, a much less significant rise in the intraocular pressure occurred as compared to the animals in which no drug was given. It means that the drug may have a prophylactic value which could be utilised to prevent an acute attack of glaucoma. The drug also prevented any further rise of the intraocular tension when it was given after production of glaucoma. The pressure rather started falling down.
It brings us to the conclusion that the administration of antilipaemic drugs like clofibrate by correcting disturbances in fat metabolism in patients in whom glaucoma is somewhat anticipated, may prevent its acute attack and may be useful to some extent as a therapeutic measure for its treatment.
| Summary|| |
Experimental glaucoma was produced in rabbits. There was a marked rise in the intraocular pressure. Clofibrate, an antilipaemic agent given before producing glaucoma prevented a marked rise in the intra-ocular pressure and given after producing glaucoma caused a decline in the intraocular pressure, thereby showing that the drug could be of significant prophylactic and also some therapeutic value.
| References|| |
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[Figure - 1]