Ganchev, T.

Mishkova, R.

Negrev, N.

English

Varna Medical University Press: Journals

PLASMA THROMBOCYTOPOIETIN A C T I V I T Y IN PATIENTS WITH CHANGED THROMBOCYTE COUNT N. Negrev, R. Mishkova, T . Ganchev Key-words: tbrombocytopoietin - idiopathic thrombocytopenic purpura - symptomatic thrombocyto­penia - essential thrombocytemia - thrombocyte count It is know that thrombocytopoietin is a specific humoral thrombocy top oie sis regulator (8). It is supposed that it presents a glucoproteide (4) and it is synthesized in kidney (9). Concern­ing its place and mechanism of action it is known that it stimulates the development of com­mitted precursors of megakaryocytes and of megakaryocytes themselves as well (7, 12). There are single investigations of plasma thrombocytopoietin activity (РТА) in healthy persons and patients with different blood diseases (1 ,5) . The aim of the present study is to follow-up РТА in patients with changed thrombocyte count. Material and Methods We determined РТА in 22 females of which 10 healthy controls and 12 patients with the fol­lowing diseases: 3 — with idiopathic thrombocytopenic purpura (ITP), 8 - with symptomatic thrombocytopenia (ST) and one with essential thrombocytemia ( E T ) . Plasma was injected to a total of 112 male mice (72 experimental and 40 control). РТА level was evaluated according to changes of 7 5 selenomethionine ( 7 5 Se-M) incorporation in newly-formed thrombocytes a^well as to thrombocyte count in peripheral blood of recipient mice. The percentage of the incorpo­rated 7 5 Se-M was determined after widely used radioisotope Penington's method (10) in our modification. To this purpose we used as recipients instead of C57-non-thoroughbred white male mice only mice with initial thrombocyte count between 200 and 380.10 9/1. Plasma was injected subcutaneously at dosis 1 ml on two consecutive days. All the mice were intraperio-neally injected 2 Ci 7 5 Se-M each one hour after the second injection. 72 hours after mat we as­pirated by means of cardiac puncture 0.5 ml blood from all the mice each under ether narcosis in order to determine the percentage of isotope incorporated. We apprehended to determine 7 5 Se-M incorporation instead on the 24th hour (as proposed by Penington) on the 72nd 0ne be­cause this period coincided with the peak of thrombocyte count increase and most manifested changes of isotope incorporation as well. Further sample processing and calculation o f 7 5 Se-M incorporation into thrombocytes was carried out completely after Penington's method. Initial thrombocyte levels were determined with all the mice at the end of experiment after Feissly and Ludin (cited after 3), too. All the animals were divided into 4 groups, namely: 1st group - injected with plasma from ITP patients; 2nd _ with plasma from ST ones; 3rd _ with plasma from E T patients, and 4th _ with plasma from healthy individuals (controls). Data obtained were processed by the methods of variation analysis. 58 N. Negrev, R. Mishkova, T . Ganchev Results and Discussion On fig. 1 and 2 one can see the data about РТА determined by the percentage of 7 5Se-M incorporated in newly-formed thrombocytes as well as thrombocyte count changes. It has to be noted that plasma from ITP and ST patients does not cause one and the same kind of chan­ges in the parameters studied in all the patients of one and the same group. More concretely, plasma of one female ITP patient causes a strong isotope incorporation increase (with 46.37 per cent, p < 0.025) and thrombocyte count one (with 32.96 per cent, p < 0.05) although there is a normal thrombocyte count in this patient. However, plasma injection from the* rest two pa­tients of this group reduces 7 5 Se-M incorporation with 73.41 per cent (p < 0.001) and throm­bocyte count with 42.50 per cent (p < 0.001) in recipient mice. Thrombocyte number is below 80.10 9/! in both patients. 75 r % in cor рог a ted Se-M 46.37% p< 0.025 i i A 37.14 % p< 0.001 34.28% p<0.05 irp ST ET 73.41% p<0.001 34.94% p< 0.025 Fip 1. РТА determined by the percentage of -Se-M incorporated in newly-formed thrombocytes of reci­pient mouse. Percentage deviation is determined in relation to the control level accepted for "0". Sign (+) indicates an increase and sign ( - ) a decrease. ST patients show also contrary' results. Plasma induces isotope incorporation increase in 62.50 per cent of them with 37.14 per cent (p < 0.001) and thrombocyte count one with 45.26 per cent (p < 0.001). There is a considerable reduction in the rest patients (36.50 per cent) of 7 5 Se-M incorporation (with 34.94 per cent, p < 0.025) and of thrombocyte count (with 41.C9 per cent, p < 0.001) as well. The mean thrombocyte number of the patients of the whole group is below 50.10 9/1. Thrombocytemic plasma injection is followed by 7 5 Se-M incorporation increase in newly formed thrombocytes of recipient mice with 34.28 per cent (p < 0.05) and by thrombocyte count one with 35.66 per cent (p < 0.025). Patient's thrombocyte number is between 700 and 1000.109/1. In our opinion, increased РТА of some ITP patients and ST ones results from a realized ne­gative feed-back mechanism induced by their thrombocytopenia (2). Besides we accept that strongly reduced РТА of the rest patients with the same diseases provides an indirect evidence for probably increased plasma inhibitory properties. This fact coincides with data reported by Plasma thrombocytopoietin. 59 other authors (1 ,6 ) . It can not be excluded mat in this case reduced РТА is due to insufficient thrombocytopoietin production. - Our data concerning РТА increase in E T cases could be explained to a certain extent by the present evidences for an increased thrombocytopoietin activity in chronic myeloid leukemia and in other diseases as well (11). According to our opinion, that is confirmation of the idea that production of specific humoral thrombocytopoiesis regulator is not regulated only by cir­culating thrombocyte number but also by bone-marrow megakaryocyte count and other fac­tors as well (2). Having in mind that 7 5 Se-M incorporation and thrombocyte count are basic indexes for РТА determination ( 1 , 12) our results obtained allow us to draw the following conclusions: 1. ITP, ST, and ET are diseases accompanied by contrary' changes of thrombocytopoietin activity; % JO to JO 20 10 +0 -o 10 20 30 uO 50 32.96 VP, I p<005 ITP Ш 12.50 ST I ̂ p<0.001 35.66 % p< 0.025 ET p<0.001 4109 Fig. 2. РТА determined by thrombocyte count changes of recipient mouse. Values are presented as percent­age deviation in relation to the control level accepted for "0". Sign (+) indicates an increase and sign ( - ) a decrease. 2. These contrary changes of thrombocytopoietin activity allow the suggestion that patho­genetic mechanisms different to a great extent are involved in these diseases. We consider РТА determination a possible additional differential-diagnostic criterion at this stage, mainly when patients with E T and to a lower extent when ST patient are concerned. R E F E R E N C E S 1. А с л a M a з о в a, E . Б., A. M. H а м я т ы ш е в а, Л. С. 1J е п а Изучение тромбоцитопоэти­ческой активности плазмы крови больных с болезнью Верльгофа до и после спленэктомии. Москва, 1982. Рукопись дсп. во ВНИИМИ, 11. 05. 1982, N 5780.м~ 2. С е л и в а н о в, В. А . , В. Г. Т я ж е л о-в а. Цитология, 26, 1984, 224-228. - 3. Т о д о р о в, Й. Клинични лабораторни изследвания в дет­ската възраст. София, Медицина и физкултура, 1962. - 4. D a s s i n, Е., J . В о u г е b i a, V. N a j е a n, A. M. R о s s е t Acta Haematol., 69, 1983, 249-253. - 5. G e w i r t z , A . , E . B r u n o , J . E l w e l l , R. H o f f m a n . Flood, 61 , 1983, 384-389. - 6. L а у е n d е с k е г, S. J . , Т. P. M с D о n a 1 d.Experim. Haematol., 10, 1982, 332-342. - 7. L о n g, M. \V. , N. W i 1 1 i a m s, Я Е b b e. Blood, 59, 1982, 569 -575. - 8. M с D o n a l d , T. P. In: Megakaryocyte biology and precursors: in vitro cloning and cellular pro­perties. Proc. Symp. Megakaryocytes in vitro. Atlanta, 1-2. V. 1980. New York, etc., Elsevier/North Hoi-60 N. Negrev, R. Mishkova, T . Ganchev land, 1981, 39-57. - 9. M с D о n a 1 d, Т. P., M . C о t t r e l l , R. С l i f t , J. К h о u г i, M, D . L o n g , J. Labor. Clin. Med., 106, 1985, 162-174. - 10. P е n i n g t о n, D. G. Brit. Med. J., 1,1970, 606-608. -l L S h r e i n e r , D . P . . J . W e i n b e r g , D. Е n о c h . Blood. 56, 1980, 183-188. - 12. T h r e a t t e G. A . , S. Е b b е , Е. P h a 1 е n. Proc. Soc. Experim. Biol Med., 167, 1981, 576-580. ТРОМБОЦИТОПОЭ.ТИНОВАЯ АКТИВНОСТЬ ПЛАЗМЫ У БОЛЬНЫХ С ИЗМЕНЕНИЕМ ЧИСЛА ТРОМБОЦИТОВ //. Нее рев, Р. Мишкова, Т. Ганчев Р Ь З Ю М Е Исследована тромбоцитопоэтиновая активность плазмы у больных с изменением числа тромбо­цитов по модифицированному авторами радиоизотопному методу Penington (1970). Тромбоцито­поэтиновая активность плазмы устанавливалась посредством 'процента включенного 75 селено-метионина в новообразованные тромбоциты и при учете числа тромбоцитов у тест-мышей под влия­нием испытуемой плазмТл. При зссенциальной тромбоцитемии устанавливается значимое повыше­ние тромбоцитопоэтиновой активности. У некоторых из больных с идеопатической тромбоцито-пенической пурпурой и симптоматической тромбоцитопенией устанавливается достоверное увели­чение тромбоцитопоэтиновой активности плазмы, а у'остальных достоверное уменьшение. Воз­можно использование этою показателя в качестве дополнительного дифференциально-диагностиче­ского критерия. 

PLASMA THROMBOCYTOPOIETIN ACTIVITY IN PATIENTS WITH CHANGED THROMBOCYTE COUNT

https://journals.mu-varna.bg/index.php/ssm/article/download/2994/2449

PLASMA THROMBOCYTOPOIETIN ACTIVITY IN PATIENTS WITH CHANGED THROMBOCYTE COUNT

Abstract

Similar works

Full text

Available Versions

Varna Medical University Press: Journals