Protein expression levels of membrane proteins in brain capillaries isolated from control, pentylenetetrazole, phenytoin, and spontaneous model of epilepsy mice
Brain capillaries were freshly isolated from approximately 3 g cerebrums pooled from 10 mice, using the glass beads column method. Whole-tissue lysates of brain capillaries (50 μg protein) were digested with trypsin to obtain peptides. The protein expression levels of the target proteins were measured by subjecting the peptide samples (33.3 or 3.33 μg protein) to liquid chromatography–tandem mass spectrometry with 500 fmol stable isotope-labeled peptide mixture. Each value represents the mean ± S.E.M. (number of analysis = 3–4).
| Molecular Names | Alternative Designation | Control | PTZ | EL | PHT | LQ |
|---|---|---|---|---|---|---|
| fmol/μg protein | ||||||
| ABC transporters | ||||||
| Abca2 | Abc2 | ULQ | ULQ | ULQ | ULQ | 0.779 |
| Abca8a | Abca8a | ULQ | ULQ | ULQ | ULQ | 0.461 |
| Abca8b | Abca8b | ULQ | ULQ | ULQ | ULQ | 0.184 |
| Abca9 | Abca9 | ULQ | ULQ | ULQ | ULQ | 0.752 |
| Abcb1a | P-gp/mdr1a | 11.5 ± 0.1 | 14.8 ± 0.6*** | 16.4 ± 0.7*** | 22.1 ± 0.6*** | — |
| Abcb1b | Mdr1b | ULQ | ULQ | ULQ | ULQ | 0.0810 |
| Abcc1 | Mrp1 | ULQ | ULQ | ULQ | ULQ | 0.302 |
| Abcc2 | Mrp2 | ULQ | ULQ | ULQ | ULQ | 1.53 |
| Abcc3 | Mrp3 | ULQ | ULQ | ULQ | ULQ | 0.0650 |
| Abcc4 | Mrp4 | 1.24 ± 0.04 | 1.23 ± 0.05 | 1.75 ± 0.06*** | 1.29 ± 0.04 | — |
| Abcc5 | Mrp5 | ULQ | ULQ | ULQ | ULQ | 0.400 |
| Abcc6 | Mrp6 | ULQ | ULQ | ULQ | ULQ | 0.151 |
| Abcg2 | Bcrp | 4.48 ± 0.36 | 5.38 ± 0.64 | 5.54 ± 0.21 | 6.96 ± 0.51** | — |
| SLC transporters and accessory proteins | ||||||
| Slc2a1 | Glut1 | 101 ± 4 | 112 ± 5 | 114 ± 4 | 127 ± 9 | — |
| Slc2a3 | Glut3 | ULQ | ULQ | ULQ | ULQ | 0.607 |
| Slc7a5 | Lat1 | 2.28 ± 0.52 | 2.21 ± 0.57 | 2.74 ± 0.71 | 2.66 ± 0.98 | — |
| Slc3a2 | 4f2hc | 11.0 ± 0.6 | 11.5 ± 0.6 | 18.4 ± 1.1*** | 13.9 ± 0.4 | — |
| Slc16a1 | Mct1 | 22.1 ± 0.7 | 17.0 ± 0.7** | 21.7 ± 0.6 | 22.4 ± 1.2 | — |
| Cd147 | Cd147 | 19.7 ± 0.3 | 16.8 ± 0.2 | 20.8 ± 0.7 | 20.0 ± 1.3 | — |
| Slco1a4 | Oatp1a4/oatp2 | 2.80 ± 0.45 | 2.50 ± 0.20 | 2.58 ± 0.35 | 2.89 ± 0.52 | — |
| Slco1c1 | Oatp1c1/oatp14 | 1.89 ± 0.08 | 1.98 ± 0.17 | 1.73 ± 0.21 | 2.09 ± 0.07 | — |
| Slco2a1 | Pgt | ULQ | ULQ | ULQ | ULQ | 0.309 |
| Slc22a8 | Oat3 | 1.29 ± 0.07 | 1.29 ± 0.06 | 1.64 ± 0.09* | 1.42 ± 0.06 | — |
| Slc27a1 | Fatp1 | 2.34 ± 0.73 | 2.18 ± 0.55 | 3.07 ± 0.35 | 2.60 ± 0.66 | — |
| Slc29a4 | Pmat | ULQ | ULQ | ULQ | ULQ | 0.0990 |
| Receptors | ||||||
| Insr | Insr | 1.50 ± 0.44 | 1.52 ± 0.40 | 1.59 ± 0.26 | 1.58 ± 0.40 | — |
| Lrp1 | Lrp1 | 0.968 ± 0.197 | 1.02 ± 0.23 | 1.26 ± 0.09 | 1.01 ± 0.13 | — |
| Tfr1 | Tfr1 | 4.45 ± 0.62 | 4.77 ± 0.25 | 4.92 ± 0.49 | 5.02 ± 0.36 | — |
| Tight junction protein | ||||||
| Claudin-5 | Claudin-5 | 7.23 ± 0.15 | 7.25 ± 0.17 | 8.31 ± 0.46 | 7.77 ± 0.30 | — |
| Other protein | ||||||
| Rlip76 | Rlip76 | ULQ | ULQ | ULQ | ULQ | 0.101 |
| Membrane marker protein | ||||||
| Na+/K+ ATPase | Na+/K+ ATPase | 29.1 ± 0.8 | 28.4 ± 0.9 | 31.5 ± 3.9 | 30.9 ± 0.4 | — |
ABC, ATP-binding cassette; LQ, limit of quantification; SLC, solute carrier; ULQ, under LQ.
↵* P < 0.05, **P < 0.01, ***P < 0.001: significantly different from the protein expression level in control mice (Dunnett’s test).