Morphological changes and viability of proximal tubular epithelial cells (PTECs). PTECs were incubated with normal human serum (NHS; 5% or 25%) or serum-free medium (controls) for 3 h with or without preincubation with P (5 μg/mL) for 3 h. There were no significant morphological changes in PTECs after the addition of up to 25% NHS. Preincubation with P before the addition of both 5% and 25% NHS did not cause morphological changes in PTECs. (a) Serum-free medium (control), (b) 5% NHS, (c) 25% NHS, (d) 5% NHS with preincubation with P and (e) 25% NHS with preincubation with P, as observed by a microscope. Pictures are representative of four-cell culture plates. Original magnification: ×50. There were no significant changes in the viability of PTECs after the addition of 5% and 25% NHS (f). Preincubation with P before the addition of both 5% and 25% NHS significantly suppressed the viability of PTECs compared with controls and 5% and 25% intact NHS (f) (**p < 0.01, *p < 0.05). Results are expressed as means ± standard errors of values from eight independent experiments.
Nagamachi et al. BMC Nephrology 2014 15:82 doi:10.1186/1471-2369-15-82