Table 1 Diabetic platelets do not express increased basal levels of α_IIbβ₃ or display enhanced responses to soluble agonist stimulation

	Agonist (µM)	Non-DM	DM	Significance
Integrin α_IIbβ₃ expression	Untreated	179.8 ± 4.52	203.3 ± 30.9	NS
Integrin α_IIbβ₃ expression	Untreated (human)	394.5 ± 24.6	488.2 ± 49.6	NS
Integrin α_IIbβ₃ activation (JON/A binding)	Untreated	5.67 ± 0.88	4.67 ± 0.67	NS
	ADP (1)	26.98 ± 1.21	27.57 ± 2.94	NS
	ADP (10)	111.2 ± 15.8	102.7 ± 19.6	NS
	PAR-4 AP (100)	14.67 ± 1.20	24.33 ± 5.23	NS
	PAR-4 AP (300)	82.33 ± 3.71	71.33 ± 1.76	NS
P-selectin expression	PAR-4 AP (100)	27.57 ± 2.90	30.11 ± 4.82	NS
P-selectin expression	PAR-4 AP (300)	50.48 ± 2.34	46.88 ± 4.69	NS
P-selectin expression (isolated platelets)	PAR-4 AP (100)	23.01 ± 2.17	28.22 ± 4.92	NS
P-selectin expression (isolated platelets)	PAR-4 AP (300)	54.36 ± 5.55	49.19 ± 5.42	NS
Aggregation (% maximal)	ADP (1)	42.4 ± 1.4	41.6 ± 3.4	NS
Aggregation (% maximal)	ADP (10)	59.3 ± 2.9	57.0 ± 10.0	NS

To assess integrin α_IIbβ₃ expression (Leo.F2 binding for mouse and HIP8 binding for human), activation (JON/A binding) and P-selectin expression in non-DM and DM platelets (mouse, if not stated otherwise), hirudinated whole blood (1/20 diluted, if not stated otherwise) or isolated washed platelets were stimulated with the indicated concentrations of ADP or PAR-4 activating peptide (PAR4-AP) for 10 min, in the presence of PE-JON/A Ab or FITC-anti-P-selectin Ab, respectively, then subjected to flow cytometry. Results are expressed as the geometric mean of fluorescence intensity. For platelet aggregation, platelet rich plasma from non-DM and DM mice were subjected to aggregometry using 1 or 10 µM ADP. Results are expressed as maximal extent of platelet aggregation (%). All results represent mean ± s.e.m. of n ≥ 3 independent mouse experiments. For human results, n = 16 for non-DMs and n = 18 for DMs. NS = not significant, p ≥ 0.05. assessed using an unpaired, two-tailed Student’s t-test.

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