Conditional disruption of interactions between Gαi2 and regulator of G protein signaling (RGS) proteins protects the heart from ischemic injury

Table 1 Preischemic and postischemic recovery of contractile function

	Preischemic			Postischemic recovery
	Gα_i2 ^{fl-G184S/fl-G184S} + tamoxifen (n = 6)	Cre-ER^T2/Gα_i2 ^{fl-G184S/fl-G184S} + tamoxifen (n = 6)	Cre-ER^T2/Gα_i2 ^{fl-G184S/fl-G184S} + vehicle (n = 4)	Gα_i2 ^{fl-G184S/fl-G184S} + tamoxifen (n = 6)	Cre-ER^T2/Gα_i2/^{fl-G184S/fl-G184S} + tamoxifen (n = 6)	Cre-ER^T2/Gα_i2 ^{fl-G184S/fl-G184S} + vehicle (n = 4)
Developed pressure (mmHg)	130 ± 6	140 ± 8	132 ± 6	45 ± 5	78 ± 8 * #	29 ± 7
+dP/dT (mmHg/sec)	6375 ± 570	6145 ± 621	4587 ± 251	2223 ± 321	3557 ± 521 #	985 ± 258
-dP/dT (mmHg/sec)	-4471 ± 291	-4601 ± 275	-3837 ± 235	-1600 ± 197	-2581 ± 263 * #	-908 ± 243
End diastolic pressure (mmHg)	5.7 ± 1.0	6.2 ± 0.9	5.0 ± 1.0	30 ± 2	21 ± 3	33 ± 7
Coronary flow rate (ml/min)	4.5 ± 0.4	4.1 ± 0.3	4.6 ± 0.4	2.7 ± 0.3	2.6 ± 0.2	2.9 ± 0.4

Preischemic contractile function was measured prior to 30 minutes of ischemia. Postischemic recovery of contractile function was measured following 1 hour of reperfusion. Data from each group were compared by one way ANOVA and posthoc Tukey analysis (preischemic and postischemic values were analyzed separately from one another). There were no significant differences between groups for any parameters of preischemic contractile function. *indicates a significant difference (p < 0.05) in postischemic recovery of contractile function compared to hearts isolated from tamoxifen treated Gα_i2 ^{fl-G184S/fl-G184S} mice. # indicates a significant difference (p < 0.01) in postischemic recovery of contractile function compared to hearts isolated from Cre-ER^T2/Gα_i2 ^{fl-G184S/fl-G184S} mice that were treated with vehicle instead of tamoxifen.

ISSN: 2050-6511