|Year : 1987 | Volume
| Issue : 2 | Page : 74-78
Aminotransferase and amylase activities of subretinal fluid and sera in rhegmatogenous retinal detachment cases
PK Chatterjee, Abhijit Ghosh, AK Dey
Deptt of Ophthalmology, N.S.R Medical College, Calcutta, India
P K Chatterjee
Deptt of Ophthalmology, N.S.R Medical College, Calcutta
Source of Support: None, Conflict of Interest: None
The study of the enzyme activity in 5 cases of normal vitreous humour, subretinal fluid and sera in 52 cases of rhegmatogenous retinal detachment lead to the following conclusions : 1) The activity of amylase in subretinal fluid tends to rise with the increase in the duration of retinal detachment There is significant difference in the amylase activity upto 24 weeks of duration, of retinal detachment 2) There is no significant change in the mean value of GOT level in SRF with the increase in the duration of retinal detachment 3) The mean GPT level of SRF decreases with the increase in the duration of retinal detachment There is a significant difference between the mean values of GPT upto 6 weeks 4) The lower value of amylase in subretinal fluid is associated with good prognosis 5) The activity of GOT in SRF has got no significant relation to the outcome of surgery. 6) The higher value of GPT in SRF is associated with good surgical results and lower value with poor result 7) There is no significant change in the concentration of amylase, GOT and GPT activity in serum in relation to the duration of retinal detachment 8) There is also no significant correlation between the level of amylase, GOT and GPT in blood depending on the result of surgery. 9) Both vitreous and blood appear to contribute to the origin of subretinal fluid.
|How to cite this article:|
Chatterjee P K, Ghosh A, Dey A K. Aminotransferase and amylase activities of subretinal fluid and sera in rhegmatogenous retinal detachment cases. Indian J Ophthalmol 1987;35:74-8
The role of serum asparate amino transferase (F-C: 22.214.171.124., GOT) and alanine aminotransferase (EC :126.96.36.199., GPT) has been much emphasised in elucidating the amount of tissue damage in cardiac and hepatic derangement These enzymes are also present in most of the body fluids invariable amounts but their functions are not yet clearly understood The activities of these aminotransferases were found to be high in the retina and uvea  while their presence was observed in vitreous also . The activity of GOT in subretinal fluid (SRF) was found to be very high in some cases of retinal detachment though no correlation could be observed when compared with the duration of the detachment . Similarly amylase (EC I: 188.8.131.52.) activity in SRF was studied  but no positive conclusion could be drawn from the study regarding the biochemical aberration associated with the accumulation of SRF. Thus it was our interest to study these enzyme contents in SRF, serum and vitreous, to find out the correlation, if any, between these enzyme activities and the duration of rhegmatogenous retinal detachment and to interpret the enzyme status in post-operative conditions
| Materials and Methods|| |
Subretinal fluids and sera were obtained from fiftytwo patients, comprising of both the sexes, who were suffering from rhegmatogenous retinal detachment Only those cases which showed no clinical or biochemical evidence of active heart and/or liver lesions were selected The age of the patients and duration of detachments, were varying from 9 years to 73 years and 1 week to 3 years respectively. The SRF was collected from these patients by means of 'an all glass, dry, sterile 5 ml syringe fitted with a , small 25- gauge needle introduced very carefully into the subretinal space. Only those cases in which the fluid was free from observable blood were included in the study. All these cases underwent scleral buckling operations Fasting venous blood was drawn from the antecubital vein of these patients during surgical procedures For control study, vitreous humour was obtained from the eye bank of the Eye Infirmary, Calcutta Medical College & Hospital, Calcutta and N.R.S. Medical College, Calcutta. Sufficient precautions were taken to see that the vitreous humour thus collected was from a relatively fresh specimen. The data obtained were interpreted under the two heads - duration of the disease and prognosis after surgery.
1. Duration of the disease
The patients were divided into five groups according to the duration of disease as ascertained from the history given by the patients as follows
Group Duration No. of Cases A Upto 2 weeks 7 B 3-6 weeks 15
C 7-12 weeks 15 D 13-24 weeks 7 E Beyond 24 weeks 8
Prognosis after surgery
The retinal detachment with good prognosis were revealed by post-operative reattachment of retina and better visual results Retinal detachments with unfavourable prognosis were revealed by postoperative non-attachment and non-improvement of visual acuity.
amylase activity of SRF, serum and vitreous humour were determined by the method described by Stewart and Dunlop . Aminotransferase activity was measured by the method of Wrobleswki et al (9) in these samples
The results were analysed statistically and 't' values were calculated. The values were expressed as mean ± standard error.
| Results|| |
The results have been indicated in [Table - 1][Table - 2][Table - 3][Table - 4][Table - 5].
| Discussion|| |
This present study shows that amino transferase activity is high in subretinal fluid. Amino transferase activities are related to the metabolism of proteins These are also enzymatic components of cellular matter. It is quite possible that in conditions leading to cellular disintegration these enzymes leak into its surroundings Naturally questions may arise whether there is any reason behind the increased concentration of these enzymes in SRF. It is expected that increased activities in SRF [Table - 1] may be partly contributed by the necrosing retinal cells The increased GOT activity might be due to application of diathermy prior to collection of SRF. Again the clinical data are not sufficient to explain the nature of relationship between SRF enzyme level and the application of such treatment But as the elevated GOT level is not related with the duration of detachment [Table - 1], it may be possible that the retinal pathology cannot be the only contributory factor for the enhanced enzymatic activity. The hypothesis of limited semi-permeability of the endothelium of chorio-capillaries and Bruch's membrane as postulated by Chignel et al  seems to be debatable as the enzyme activities in serum as well as in normal vitreous were well within normal limits [Table - 5]. However the authors (3) found Ig G (Mol. wt - 150,000) in every case, higher molecular weight proteins being absent in all rhegmatogenous detachment cases Molecular weight of aspartate aminotransferase is 110,000 and that of amylase is 45000 and therefore it is not surprising that they are found in SRF.
It is interesting to note that the mean GPT level in SRF came down significantly after 2 weeks of detachment [Table - 1]. In the early stage of detachment its value in SRF is found to be more than that of GOT. The mean GPT value shows a downward trend with the increase in the duration of detachment [Table - 1].
The mean value of GOT in SRF is higher in the successful groups of cases than the unsuccessful eyes [Table - 3], but this is statistically insignificant [Table - 3]. The GPT level of SRF in successful cases is much higher than that of unsuccessful cases [Table - 3] and there is a definite correlation between the level of GPT with the success after surgery [Table - 3]. The higher values are associated with good prognosis It is well known that in hepatic disorders like infective hepatitis, altered GOT/GPT ratio is taken to be the index for the assessment of prognosis The cellular concentration of GOT and GPT in retinal epithelium has not yet been quantitatively assessed in human eyes though its qualitative presence has been described by Muto (6) in rabbit retina. It is not unlikely that with the advancement of duration of detachment retinal cellular atrophy progresses with concomitant fall in GPT values The GOT/GPT ratio can be used as an index for determining the age as well as prognosis of detachment Retinal detachment cases with unsuccessful results showed decreased amino-transferase activity with increased GOT/ GPT ratio, the exception being in Group B [Table - 4]. If it is assumed that retinal detachment with bad prognosis is related with increased atrophy, then GOT and GPT levels in SRF, as well as their ratios, can well be taken as the indices, for the assessment of the prognosis in retinal detachment.
The amylase activity in SRF is found to gradually rise with the increase in the duration of retinal detachment [Table - 1] and this increase is statistically significant upto 24 weeks [Table - 1]. After 24 weeks the value tends to fall, but the fall is insignificant The mean amylase content of SRF is significantly lower in the successful group of cases than in the unsuccessful group [Table - 3]. The possible role of the enzyme is yet to be explained. It has not yet been ascertained until now, whether there is any correlation between this enzyme and the mucopolysaccharides present in the retinal epithelium.
Though in the early stages the amylase may be contributed by the vitreous body, the choriocapillaries are probably taking part in subsequent stages of the development of SRF [Table - 5].
| References|| |
Bastide, P. Clermount Ferrand (1961); Cited by Duke-Elder, S.S, System of Ophthalmology, IV, 27, 1968, Kimpton, London.
Cabaud, P.; Leeper, R and Wroblewski, F. Amer J. clin. Path, 26, 1101, 1956.
Chignel, AR; Carruthers, M and Rahi, AH.S. Brit, J. OphthaL, 56, 526, 1971.
Kaufman, P.L; Podos, S.M. Survey OphthaL, 18,100, 1973.
Manna, F.; Janusziewicz, L and Mielnikowa, L Kiln. oczna, 37, 617, 1967.
Muto, R Acta Soc OphthaL Jap., 64, 42, 1960
Stewart, CP. and Dunlop, D. Clinical Chemistry in Practical Medicine, Sixth Ed., 321,1962, E & S. Uvingstone Ltd., Edinburgh and London.
Weve, H.J.M. and Fischer, F.P. Arch. F. Augenheilk, 110, 198, 1936.
Wroblewski, F. and Cabaud. P. Amer. J. Clin. Path., 29, 223, 1957.
[Table - 1], [Table - 2], [Table - 3], [Table - 4], [Table - 5]