Table 3. MALDI-TOF MS/MS analysis of fifteen altered protein spots in PNS prepared from hippocampus of rats exposed to morphine for 10 days and sacrificed 20 days after the last dose; difference of protein composition in PNS samples prepared from groups (+M10/−M20) and (−M10/−M20).

Spot	Accession number	Protein name	Mascot score	Matched peptides	SCa [%]	MWb (kDa)	pIc	Change (fold)	p value
1	SYUB_RAT	Beta-synuclein	96	5	29	14.5	4.48	↓ 2.4	0.0259
2	SYUA_RAT	Alpha-synuclein	249	5	36	14.5	4.74	↓ 5.3	0.0038
3	TBA1A_RAT	Tubulin alpha-1A chain	298	19	40	50.8	4.94	↓ 4.5	0.0023
4	F1M953_RAT	Stress-70 protein, mitochondrial	423	15	15	74.0	5.87	↑ 2.1	0.0291
5	PDIA3_RAT	Protein disulfide-isomerase A3	117	10	13	57.0	5.88	↓ 2.2	0.0286
6	ATP5H_RAT	ATP synthase subunit d, mitochondrial	305	8	31	18.8	6.17	↓ 2.0	0.0167
7	SODC_RAT	Superoxide dismutase [Cu-Zn]	81	6	31	16.1	5.88	↓ 3.1	0.0490
8	DPYL2_RAT	Dihydropyrimidinase-related protein 2	237	9	17	62.6	5.95	↓ 2.4	0.0251
9	ENOA_RAT	Alpha-enolase	694	20	28	47.4	6.16	↑ 3.1	0.0154
10	EFTU_RAT	Elongation factor Tu, mitochondrial	242	8	13	49.9	7.23	↓ 2.2	0.0164
11	D3ZGY4_RAT	Glyceraldehyde-3-phosphate dehydrogenase	109	9	9	36.1	7.63	↓ 2.4	0.0168
12	D3ZGY4_RAT	Glyceraldehyde-3-phosphate dehydrogenase	273	6	10	36.1	7.63	↓ 2.3	0.0087
13	D3ZGY4_RAT	Glyceraldehyde-3-phosphate dehydrogenase	316	13	20	36.1	7.63	↓ 4.1	0.0180
14	COF1_RAT	Cofilin-1	346	9	40	18.7	8.22	↓ 2.8	0.0115
15	ALDOA_RAT	Fructose-bisphosphate aldolase A	255	24	53	39.8	8.31	↓ 2.8	0.0104

^a sequence coverage,

^b theoretical molecular weight,

^c theoretical isoelectric point; complete list of peptides used for identification is presented in S2 Table.