Heterotrimeric G-proteins play a crucial role in the control of renal epithelial cell function during homeostasis and in response to injury. In this report, G-protein bg subunit (Gbg) dimer activity was evaluated during the process of tubular repair after renal ischemia-reperfusion injury (IRI) in male Sprague Dawley rats. Rats were treated with a small molecule inhibitor of Gbg activity, gallein (30 or 100 mg/kg), 1 hour after reperfusion and every 24 hours for 3 additional days. After IRI, renal dysfunction was prolonged after the high-dose gallein treatment in comparison with vehicle treatment during the 7-day recovery period. Renal tubular repair in the outer medulla 7 days after IRI was significantly (P , 0.001) attenuated after treatment with high-dose gallein (100 mg/kg) in comparison with low-dose gallein (30 mg/kg), or the vehicle and fluorescein control groups. Gallein treatment significantly reduced (P , 0.05) the number of proliferating cell nuclear antigen-positive tubular epithelial cells at 24 hours after the ischemia-reperfusion phase in vivo. In vitro application of gallein on normal rat kidney (NRK-52E) proximal tubule cells significantly reduced (P , 0.05) S-phase cell cycle entry compared with vehicletreated cells as determined by 59-bromo-29-deoxyuridine incorporation. Taken together, these data suggest that Gbg signaling contributes to the maintenance and repair of renal tubular epithelium and may be a novel therapeutic target for the development of drugs to treat acute kidney injury.

How do racial signals associating a candidate with minority supporters change voters' perceptions about a candidate and their support for a candidate? Given the presence of competing information in any campaign or the absence of information in low-salience campaigns, voters may rely on heuristics-such as race-to make the process of voting easier. The information communicated by these signals may be so strong that they cause voters to ignore other, perhaps more politically relevant, information. In this paper, we test how associative racial cues sway voters' perceptions of and support for candidates using two experiments that harness real-world print and audio campaign advertisements. We find that the signals in these ads can sometimes overwhelm cues about policy positions when the two are present together. Moreover, we find that such signals have limited effects on candidate support among black voters but that they risk substantial backlash of up to eight percentage points in reported vote intention among white voters. Our results highlight how voters gather and use information in low-information elections and demonstrate the power of campaign communication strategies that use racial associations.

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