Background: Classical β-blockers usually reduce renal blood flow thus, worsening renal function in hypertensive patients with renal impairment. However, vasodilator b-blockers with biased agonist activity on b-arrestin, at least theoretically, could protect the kidney against ischemia.
Objectives: To compare the effect of prophylactic administration of carvedilol, nebivolol, nadolol on the kidneys. Materials & Methods: Rats were divided into five groups: Group1: sham-operated; Group2: Untreated hypertensive; Group3: Carvedilol pre-treated; Group4: Nebivolol pre-treated; Group5: Nadolol pre-treated. MABP, serum urea, creatinine, renal level of TNFα, BAX and pERK1/2 to non-pERK1/2 ratio were measured, besides renal histopathology and Bax immunohistochemistry.
Results: In carvedilol and nebivolol groups, MABP, Bax, TNFα and pERK1/2 to non-pERK1/2 ratio were not only significantly (P<0.05) lower than that of the untreated group; but also, not significantly different from that of the sham; except significantly higher pERK1/2 to non-pERK1/2 ratio. In the nadolol pre-treated rats, MABP and the pERK1/2 to non-pERK1/2 ratio were significantly lower than that of the untreated hypertensive rats, however, they were significantly higher than that of the carvedilol, nebivolol pre-treated groups and the sham-operated group. Furthermore, Bax and TNFα were not significantly different from that of the untreated hypertensive group; in the meantime, they were significantly higher compared to sham, carvedilol and nebivolol pretreated groups. Serum urea& creatinine levels were significantly higher in nadolol pre-treated group compared to other groups. 
Conclusion: Carvedilol and nebivolol have renal protective effect which is nearly equal in contrast to the deterioration caused by nadolol.