Antiplatelet Effect of Lonchocarpin and Derricin Isolated from Lonchocarpus sericeus.

Figures & data

Figure 1 Chemical structures of lonchocarpin (a) and derricin (b).

Table 1.. Effect of LCC and DRC on adenosine 5′-diphosphate (ADP)-, adrenaline (ADR)-, thrombin (THR)-, collagen (COL)- and arachidonic acid (AA)-induced platelet aggregation in human PRP.

		% Aggregation
Group		ADP (20 µM)	ADR (30 µM)	THR (0.16 U/mL)	COL (42.6 µg/mL)	AA (30 µM)
LCC	200 µg/mL	68.1 ± 1.44^a.	76.5 ± 2.27^a.	81.8 ± 2.52^a.	85.0 ± 2.68^a.	77.3 ± 3.52^a.
	400 µg/mL	55.5 ± 2.55^a.	58.7 ± 1.07^a.	64.0 ± 3.16^a.	79.8 ± 3.75^a.	64.9 ± 3.22^a.
DRC	200 µg/mL	65.7 ± 6.82^a.	70.8 ± 3.33^a.	77.8 ± 3.95^a.	85.6 ± 2.99^a.	67.6 ± 3.03^a.
	400 µg/mL	50.8 ± 1.64^a.	56.0 ± 1.63^a.	55.0 ± 1.88^a.	76.9 ± 2.80^a.	47.5 ± 1.85^a.

After LCC, DRC or Crel 2% (Control) preincubated with PRP at 37°C for 5 min, inducers were added and the reaction was registered for 8 min. Values are presented as mean ± S.E.M. of aggregation percentages relative to control (100%) of 5 to 8 experiments.

^a.Significantly different from controls.

Table 2.. Effect of preincubation with L-arginine on antiaggregating actions of LCC or DRC.

Group	% Aggregation
LCC (200 µg/mL)	77.5 ± 2.22^a.
DRC (200 µg/mL)	75.5 ± 1.34^a.
L-arg (9.7 µg/µl)	84.0 ± 4.94^a.
L-arg + LCC	72.1 ± 2.77^a.
L-arg + DRC	60.2 ± 4.13^a.,^b.

PRP was preincubated with L-arginine (L-arg 9.7 µg/µl) for 3 min at 37°C before the addition of Crel 2%, LCC or DRC (200 µg/mL) which were added 5 min before ADP (20 µM). Data were expressed as mean ± SEM of aggregation percentages relative to control (100%) of 4 to 10 experiments.

^a.Significantly different from the control group.

^b.Significantly different from the L-arg group.

Table 3.. Effect of preincubation with pentoxifylline on antiaggregating actions of LCC or DRC.

Group	% Aggregation
LCC (200 µg/mL)	79.7 ± 3.55^a.
DRC (200 µg/mL)	82.1 ± 4.02^a.
PTX (377 µg/mL)	90.6 ± 4.05
PTX + LCC	58.9 ± 3.55^a.,^b.
PTX + DRC	52.6 ± 5.06^a.,^c.

After pentoxifylline (PTX 377 µg/mL) preincubated with PRP at 37°C for 3 min, LCC (200 µg/mL), DRC (200 µg/mL) or Crel 2% were added for another 5 min, before the inducer ADP (20 µM). Values are mean ± SEM of aggregation percentages relative to control (100%) of 5 to 7 experiments.

^a.Significantly different from the control group.

^b.Significantly different from the LCC group.

^c.Significantly different from the DRC group.

Table 4.. Effect of preincubation with aspirin on antiaggregating actions of LCC or DRC.

Group	% Aggregation
LCC (200 µg/mL)	73.5 ± 3.30^a.
DRC (200 µg/mL)	73.6 ± 3.52^a.
ASP (20 µM)	94.6 ± 4.16
ASP + LCC	73.3 ± 2.73^a.,^b.
ASP + DRC	70.4 ± 5.46^a.,^b.

PRP was preincubated with aspirin (ASP 20 µM) for 3 min at 37°C before the addition of Crel 2%, LCC or DRC (200 µg/mL) which were added 5 min before AA (30 µM). Values are mean ± SEM of aggregation percentages relative to control (100%) of 5 experiments.

^a.Significantly different from the control group.

^b.Significantly different from the ASP group.

Table 5.. Effect of preincubation with yohimbine on antiaggregating actions of LCC or DRC.

Group	% Aggregation
LCC (200 µg/mL)	82.8 ± 3.48^a.
DRC (200 µg/mL)	78.7 ± 4.61^a.
YOH (2.1 µM)	94.4 ± 2.10
YOH + LCC	85.7 ± 5.66^a.
YOH + DRC	77.3 ± 5.10^a.

After yohimbine (YOH 2.1 µM) preincubated with PRP at 37°C for 3 min, LCC (200 µg/mL), DRC (200 µg/mL) or Crel 2% were added for another 5 min, before the inducer adrenaline (ADR 30 µM). Values are mean ± SEM of aggregation percentages relative to control (100%) of 5 to 7 experiments.

^a.Significantly different from the control group.