Dietary fat and arterial thrombosis: Role of blood clotting

~~vI~~SIS

RESEARCH

Supplement Number 1 LIPIDS AND THROMBOSIS, Troma)

Vol.4,1874 Pergamon Press

DIETARY FAT AND ARTERIAL THROMBOSIS: ROLE OF BLOOD CLOTTING G. Hornstra Unilever Research, Vlaardingen, The Netherlands

Dietary fats affect arterial thrombus formation, most probably via their effect on platelet aggregation. In venous thrombosis a contributing role of coagulation, especially platelet factor 3 (PF 3) activity, has been suggested. To investigate whether dietary fats act on arterial thrombosis likewise via an effect on coagulation, studies were done in rats fed diets containing 50 Cal% (24 w/w X) of either sunflowerseed oil (SO) or hydrogenated coconut oil (HCO), inducing a low and high thrombosis tendency respectively. After 8 weeks of feeding, thrombosis- and coagulation parameters were determined. The results (Table I), show a significant difference in arterial thrombosis tendency, but no difference in the coagulability of whole blood (Chandler loop) and in the recalcification plasma clotting time (PCT) in platelet-rich plasma (PRP) and in the PRP+platelet-poor plasma (PPP) mixture. In PPP, however, PCT in the HCO group is significantly longer than in the SO group. Similar results were obtained after 4 weeks of feeding. The difference in PCT between PPP and PRP+PPP is apparently due to the clotpromoting effect of 0.3 x IO6 blood platelets/ul. In the HCO-group this platelet-induced PCT-decrease (154 s 2 26.7) is significantly (P2 < 0.05) higher than that in the SO-group (82 s f 22.1), indicating that the procoagulant

activity of "HCO-platelets" is higher than that of "SO-platelets".

This is not due to an enhanced PF3-availability, as this platelet property is significantly depressed in the HCO-group. Since in both groups the thromboplastin - and stypven times are essentially the same, the prolonged PCT in platelet poor HO-plasma

as compared with SO-plasma may probably be due to

some deficiency of the intrinsic clotting system. The fact that "HCO-platelets" can almost completely correct for this deficiency suggests that as compared with "X+-platelets", more plasmatic clotting factors are absorbed to'their surface. 69

Supplement Number 1, Vol. 4,1974

70

Table

1

Thrombosisand Coagulation Parameters measured in Rats fed Diets containing 50 calZ,of either Sunflowerseed Oil (SO) or Hydrogenated Coconut Oil (HCO) for 8 Weeks. (Mean f SEM. n = 12-16). Parameter

Unit

Art. thromb. tend. (OT, 1)

so

log h

2.272f0.055

h Clot

formation

time

PRP: platelet

(2)

count

S

106/,1

PCT(3)

HCO 1.992,+0.051

< 0.001

187

98

15Oi4.8

142-+7.2

> 0.10

2.06’?0.082

s 0.10

16227.2

> 0.10

2.00

‘0.150

14ti6.6

8

P?

PRP+PPP: platelet

count

106J,1

0.29

-+0.050

0.29

20.028

> 0.10

PCT(3)

S

186Z6.0

20227.5

> 0.10

PPP: PCT(3)

S

275220.7

356224.6

< 0.05

102.421.36

104.4,+1.58

> 0.10

0.84,+0.037

0.95

20.024

< 0.05

32.020.6

31.0

20.5

> 0.10

thromboplastin time

x*

blood: platelet stypven

*loo% Because

time

106/,1

(ST)

S

ST, collagen

2’

X

of

ST

89.022.1

97.3

21.9

< 0.01

ST, collagen

6’

II of

ST

76.0tl.5

86.2

22.1

< 0.01

ST, collagen

10’

X of

ST

77.221.3

85.0

22.0

< 0.01

ST, collagen

14’

X of

ST

76.321 .O

82.6

22.0

< 0.05

= 20.4s

(SEM ? 0.20,

of

higher

gulation larly

count

this

in dietary

n=l6)

.

pro-coagulant

fat

affected

not when, as in arterial

activity

a contributing

thrombogenesis thrombus formation,

cannot

role

of

be excluded,

many platelets

coaparticu-

have clumped

together. References 1. HORNSTRA,G. and VENDELMANS-STARRBNB URG, A. Induction arterial

occlusive

2. CBANDLER,A.B. 110,

thrombi

In vitro

in rats.

thrombotic

kth?JWb~ehObi.b

coagulation

of experimental 1973.

369,

2:

of blood.

Lab.

Inve6.L

1,

1958.

3. RENAUD, S. The recalcification clotting

test

in man and rats.

plasma clotting Can. J. P&ibiOioe.

time.

A valuable

PfwtmacoL

47,

general 689,

1969.