INTRODUCTION: A novel in vitro system was developed to measure O₂ consumption by murine tissues over several hours. METHODS: Tissue specimens (7-35 mg) excised from male Balb/c mice were immediately immersed in ice-cold Krebs-Henseleit buffer, saturated with 95% O₂:5% CO₂. The specimens were incubated at 37 °C in the buffer, continuously gassed with O₂:CO₂ (95:5). [O₂] was determined as a function of time from the phosphorescence decay rates (1/τ) of Pd(II) meso-tetra-(4-sulfonatophenyl)-tetrabenzoporphyrin. The values of 1/τ were linear with [O₂]: 1/τ=1/τo + kq [O₂]; 1/τo=the decay rate for zero O₂, kq=the rate constant in s⁻¹ μM⁻¹. RESULTS: NaCN inhibited O₂ consumption, confirming oxidation occurred in the mitochondrial respiratory chain. The rate of respiration in lung specimens incubated in vitro for 3.9≤t≤12.4 h was 0.24±0.03 μM O₂ min⁻¹ mg⁻¹ (mean±SD, n=28). The corresponding rate for the liver was 0.27±0.13 (n=11, t≤4.7 h), spleen 0.28± 0.07 (n=10, t≤5h), kidney 0.34±0.12 (n=7, t≤5h) and pancreas 0.35±0.09 (n=10, t≤4h). Normal tissue histology at hour 5 was confirmed by light and electron microscopy. There was negligible number of apoptotic cells by caspase 3 staining. DISCUSSION: This approach allows accurate assessment of tissue bioenergetics in vitro.
INTRODUCTION: A novel in vitro system was developed to measure O₂ consumption by murine tissues over several hours. METHODS: Tissue specimens (7-35 mg) excised from male Balb/c mice were immediately immersed in ice-cold Krebs-Henseleit buffer, saturated with 95% O₂:5% CO₂. The specimens were incubated at 37 °C in the buffer, continuously gassed with O₂:CO₂ (95:5). [O₂] was determined as a function of time from the phosphorescence decay rates (1/τ) of Pd(II) meso-tetra-(4-sulfonatophenyl)-tetrabenzoporphyrin. The values of 1/τ were linear with [O₂]: 1/τ=1/τo + kq [O₂]; 1/τo=the decay rate for zero O₂, kq=the rate constant in s⁻¹ μM⁻¹. RESULTS:NaCN inhibited O₂ consumption, confirming oxidation occurred in the mitochondrial respiratory chain. The rate of respiration in lung specimens incubated in vitro for 3.9≤t≤12.4 h was 0.24±0.03 μM O₂ min⁻¹ mg⁻¹ (mean±SD, n=28). The corresponding rate for the liver was 0.27±0.13 (n=11, t≤4.7 h), spleen 0.28± 0.07 (n=10, t≤5h), kidney 0.34±0.12 (n=7, t≤5h) and pancreas 0.35±0.09 (n=10, t≤4h). Normal tissue histology at hour 5 was confirmed by light and electron microscopy. There was negligible number of apoptotic cells by caspase 3 staining. DISCUSSION: This approach allows accurate assessment of tissue bioenergetics in vitro.
Authors: Mohammed T Al Samri; Rafael Silva; Saeeda Almarzooqi; Alia Albawardi; Aws Rashad Diab Othman; Ruqayya S M S Al Hanjeri; Shaikha Km Al Dawaar; Saeed Tariq; Abdul-Kader Souid; Tewodros Asefa Journal: Int J Nanomedicine Date: 2013-03-21
Authors: Mohammed T Al Samri; Ankush V Biradar; Ahmed R Alsuwaidi; Ghazala Balhaj; Suleiman Al-Hammadi; Safa Shehab; Suhail Al-Salam; Saeed Tariq; Thachillath Pramathan; Sheela Benedict; Tewodros Asefa; Abdul-Kader Souid Journal: Int J Nanomedicine Date: 2012-08-03
Authors: Ahmed R Alsuwaidi; Mohammed T Alsamri; Ali S Alfazari; Saeeda Almarzooqi; Alia Albawardi; Aws R Othman; Thachillath Pramathan; Stacey M Hartwig; Steven M Varga; Abdul-Kader Souid Journal: BMC Res Notes Date: 2013-01-12