Table 1.

Peak changes in heart rate and overall developed tension during 30 s of static contraction of the hindlimb muscles before and after injecting P2X receptor, ASIC3 channel, and/or EP4 receptor inhibitors into the femoral artery

	ΔHR, beats/min		TTI, kg · s
Drug	Before	After	Before	After	n
PPADS (10 mg/kg)	11.6 ± 3 (352 ± 14*)	10.6 ± 3 (347 ± 19*)	23.8 ± 3	23.6 ± 2	5
APETx2 (100 μg/kg)	9.7 ± 3 (375 ± 22*)	6.5 ± 2 (368 ± 19*)	22.1 ± 2	22.1 ± 2	6
L161982 (2 μg/kg)	6.2 ± 3 (351 ± 22)	11.2 ± 5 (347± 24)	19.0 ± 3	18.7 ± 3	6
PPADS (10 mg/kg ia), APETx2 (100 μg/kg ia), and L161982 (2 μg/kg ia)	11.3 ± 3 (348 ± 27*)	7.6 ± 2 (326 ± 24*)	21.0 ± 2	21.3 ± 2	7
PPADS (10 mg/kg iv), APETx2 (100 μg/kg iv), and L161982 (2 μg/kg iv)	22.6 ± 6 (363 ± 31*)	17.8 ± 3 (372 ± 22)	20.3 ± 3	21.9 ± 3	5

Baseline values (means ± SE) for mean arterial pressure and heart rate (HR) are reported in italics next to peak change. ASIC3, activating acid-sensing ion channel 3; TTI, tension-time index.

^*P < 0.05, HR increased significantly over baseline values.