Table 2.

IC₅₀-values for inhibition of phosphodiesterase-3 (PDE3), phosphodiesterase-5 (PDE5), and inhibition of cAMP- and cGMP-efflux at temperatures ranging from 37 to 20 °C

Temperature	PDE3	PDE5	cAMP-efflux	cGMP-efflux
37 °C	15.8 ± 4.25	7.70 ± 0.265	1.33 ± 0.566	0.531 ± 0.338
34 °C	14.2 ± 1.51	10.7 ± 1.92	3.61 ± 2.59	0.893 ± 0.401
32 °C	26.7 ± 4.70	15.5 ± 0.753	2.01 ± 0.819	0.724 ± 0.206
28 °C	22.4 ± 6.36	24.3 ± 5.58	1.93 ± 1.11	0.851 ± 0.281
24 °C	29.2 ± 4.72	25.2 ± 6.57	–	0.502 ± 0.315
20 °C	31.0 ± 9.47	39.4 ± 10.9*	–	0.388 ± 0.070

Values are mean ± SEM and given in µM. * Significant difference (p-value < 0.05), when compared to normothermic baseline. No inhibition of ABCC4-activity was detectable below 28 °C