A.B. Rehman ( Department of Pharmacology, Faculty of Pharmacy, University of Karachi, Karachi-32. )
S.I Ahmad ( Department of Pharmacology, Faculty of Pharmacy, University of Karachi, Karachi-32. )
Haematological effects of 0.025% warfarin, 0.0375% coumatetralyl and 0.005% difenacoum on the blood picture of Tatera indica was studied. The blood changes in survivors treated with anticoagulants, induced noticeable changes in the blood picture as expressed by reduction of haemoglobin value, red cell count, and increase in leucocytes. The platelets exhibited a similar trend to that of erythrocytic count showing an early phase of thrombocytopenia associated with prolongation of bleeding, coagulation and prothrombin time (JPMA 33:203, 1983).
Susceptibility of Tatera indica differ in response to different anticoagulants, and it was found that Tatera indica is more susceptible to difenacoum than warfarin and coumatetralyl. Male Tatera indica is supposed to be the most tolerant to warfarin (Greaves and Rehman, 1977).
This work deals with the consequences of anticoagulant effects on the blood picture of Tatera indica with three different anticoagulants as a basis from biological discrimination between various anticoagulants. In the present investigation the effect of warfarin coumatetralyl and difenacoum have been studied.
Material and Methods
Mature medium weight group of male rats, Tatera indica being the most tolerant, was selected for the present study. The animnals were experimentally exposed to different feeding periods i.e., 2, 4, 6, 8, 10 and 15 days respectively. The animals were caged individually and were supplied with water and laboratory diet. The animals first given plain flour so as to establish feeding. After 2 or 3 days the flour mixed with the toxic compound was supplied and exact amount of anticoagulant used from toxic diet was calculated. Blood was drawn from the survived animals and haemoglobin was determined, erythrocytes, leucocytes and differential count were made by counting chamber, prothrombin time was measured by Simplastin, using Quick one stage time, coagulation was measured by using capillary glass tube method and bleeding time was determined by Duke’s method.
The blood picture of the survivors treated with 0.025% warfarin, 0.0375% coumatetralyl and 0.005% difenacoum was studied for 48 hours after treatment then on 4, 6, 10 and 15 days respectively. In the same way the blood picture of controlled were examined. The haemotological techniques suggested by Britton (1963) and Seiverd (1964) was observed in the present studies.
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