Table S1 Effect of LY341495, ketamine or NBQX on spontaneous locomotor activity

Drugs Locomotor counts (60 min)

Vehicle A (i.p.) 13096.7 ± 1198.2

LY341495 (1 mg/kg, i.p.) 10666.5 ± 797.2

LY341495 (3 mg/kg, i.p.) 11326.7 ± 660.6

Vehicle B (i.p.) 10407.3 ± 685.1

Ketamine (30 mg/kg, i.p.) 12741.0 ± 1645.3

Vehicle B (s.c.) 11783.2 ± 1866.6

NBQX (10 mg/kg, s.c.) 11692.7 ± 2031.4

Vehicle C (0.1 mL/side) 13845.8 ± 917.9

LY341495 (0.03 pmol/side) 13758.8 ± 2225.4

Ketamine (3 nmol/side) 13763.5 ± 1193.4

Table S1

Effect of LY341495, ketamine or NBQX on spontaneous locomotor activity

For systemic administration, LY341495 (1, 3 mg/kg i.p.) or ketamine (30 mg/kg i.p.) was administered 30 min prior to the test. NBQX (10 mg/kg, s.c.) was administered 35 min prior to the test. For microinjection, LY341495 (0.03 pmol/side) or ketamine (3 nmol/side) was administered into the mPFC 30 min prior to the test. NBQX (0.03 nmol/side) was administered into the mPFC 35 min prior to the test. Vehicle A: 1/15 M phosphate buffer, Vehicle B: saline, Vehicle C: Ringer’s solution. Values indicate the mean ± S.E.M. (n = 6).

Table S2 Effect of LY341495 or ketamine on the c-Fos immunoreactivity colocalized with 5-HT neuron cells in the dorsal raphe nucleus.

― + NBQX (0.03 nmol/side)

LY341495 (0.03 pmol/side) ↑ n.d.

Ketamine (3 nmol/side) ↑ n.d.

NBQX (0.03 nmol/side) → n.d.

LY341495 (1 mg/kg, i.p.) ↑ Block

Ketamine (30 mg/kg, i.p.) ↑ Block

Drugsc-Fos/5-HT

Table S2

Effect of of LY341495 or ketamine on the c-Fos immunoreactivity colocalized with 5-HT neuron cells in the dorsal raphe nucleus.

For microinjection, LY341495 (0.03 pmol/side) or ketamine (3 nmol/side) was administered into the mPFC 90 min prior to the test. NBQX (0.03 nmol/side) was administered into the mPFC 95 min prior to the test. For systemic administration, LY341495 (1, 3 mg/kg i.p.) or ketamine (30 mg/kg i.p.) was administered 90 min prior to the test. NBQX (10 mg/kg, s.c.) was administered 95 min prior to the test. →: not affected, ↑: increase, n.d.: not determined, (n = 6).

Figure S1

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Effect of LY341495, ketamine, or paroxetine in the FST.

Effect of LY341495 (a), ketamine (b) or paroxetine (c). LY341495 (0.1, 0.3, 1, 3 mg/kg i.p.), ketamine (3, 10, 30 mg/kg i.p.) or paroxetine (1, 3, 10 mg/kg i.p.) was administered 24 h prior to the test. Vehicle = (a): 1/15 M phosphate buffer (pH 8.0), (b): saline, (c): distilled water. Values indicate the mean ± S.E.M. ((a): n = 8, (b): n = 8, (c): n = 8). **p < 0.01, ***p < 0.001 compared with each vehicle (Dunnett’s test).

Effect of 5-HT depletion on the antidepressant effect of LY341495 (d) or ketamine (e). LY341495 (3 mg/kg i.p.) or ketamine (30 mg/kg i.p.) was administered 24 h prior to the test. PCPA (300 mg/kg i.p.) was administered twice daily for 3 consecutive days until the day before the test. Vehicle = (d): 1/15 M phosphate buffer (pH 8.0), (e): saline. Values indicate the mean ± S.E.M. ((d): n = 10, (e): n = 10). ***p < 0.001 compared with 0.5% MC-treated each vehicle, ###p < 0.001 compared with 0.5% MC-treated agents ((d): LY341495, (e): ketamine) (LSD post hoc test).

Figure S1

Figure S2

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Effect of microinjection of LY341495 or ketamine into the mPFC in the FST.

LY341495 (0.03 pmol/side) or ketamine (3 nmol/side) was administered into the mPFC 24 h prior to the test. Vehicle = (a): 0.1% 1/15 M phosphate buffer (pH 8.0) in Ringer’s solution, (b): Ringer’s solution. Values indicate the mean ± S.E.M. ((a): n = 7-8, (b): n = 8). ***p < 0.001 compared with each vehicle (Student’s t-test). (c, d) Location of the microinjection cannula tips in the mPFC included in the analyses of the data illustrated in ((c) = (a), (d) = (b). The line drawings are from Paxinos and Franklin (1997). The numbers to the right are the millimeters from the bregma. The open square represents the location of the microinjection cannula tips.

Figure S2

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Figure S3

Location of the microinjection cannula tips in the mPFC included in the analyses of the data illustrated in (Table S1).

The line drawings are from Paxinos and Franklin (1997). The numbers to the right are the millimeters from the bregma. The open square represents the location of the microinjection cannula tips of the vehicle C, LY341495 and ketamine-microinjection group.

Figure S3

Figure S4

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c-Fos 5-HT c-Fos/5-HT

Intra-mPFC (20×)

Effect of microinjection of LY341495 or ketamine on the c-Fos immunoreactivity colocalized with 5-HT neuron cells in the dorsal raphe nucleus.

Confocal images of c-Fos (red), 5-HT cells (green) and double (5-HT-c-Fos, colocalization) immunoreactivities in the DRN at around -4,72 mm from bregma (Scale bar: 100 mm)

Figure S4

Figure S5

c-Fos 5-HT c-Fos/5-HT c-Fos 5-HT c-Fos/5-HT

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(20×) (20×)

Effect of microinjection of an AMPA receptor antagonist on LY341495 or ketamine-induced c-Fos immunoreactivity colocalized with 5-HT neuron cells in the dorsal raphe nucleus.

(a, b) Confocal images of c-Fos (red), 5-HT cells (green) and double (5-HT-c-Fos, colocalization) immunoreactivities in the DRN at around -4,72 mm from bregma (Scale bar: (a, b) 100 mm).

Figure S5