Table 1 Methodological specifications of ex vivo field recordings in the Schaffer collateral pathway, using Gq- and Gi-DREADD based astrocyte modulation

Viral vectors and used chemogenetic tools

Viral vector with DREADD construct

*Gq-DREADD: AAV8-GFAP-hM3Dq-mCherry

*Gi-DREADD: AAV8-GFAP-hM4Di-mCherry

*Control vector: AAV8-GFAP-mCherry

*Gq-DREADD: AAV8-GFAP-hM3Dq-mCherry

*Gi-DREADD: /

*Control vector: AAV8-GFAP-mCherry

*Gq-DREADD: /

*Gi-DREADD: AAV-GFAP-hM4Di-mCherry

*Control vector: AAV-GFAP-GFP

Animals

Mouse strain/age

C57Bl6J/11–13 weeks

C57Bl6J/11–13 weeks

C57Bl6J/7–8 weeks

Gender

Male

Male

Male

Group/single housed

Group

Group

Ns

Slicing conditions

Slice orientation and thickness

Coronal

400 µm

Coronal

400 µm

Transverse

350–400 µm

Slicing solution (in mM)

75 Sucrose, 87 NaCl, 2.5 KCl, 25 NaHCO₃, 1.25 NaH₂PO₄, 7 MgCl₂, 0.5 CaCl₂, 0.6 Ascorbic acid and 25 glucose

126 NaCl, 2.6 KCl, 26 NaHCO₃, 1.25 NaH₂PO₄, 1 MgCl₂, 0.625 CaCl₂ and 10 glucose

212.7 sucrose, 5 KCl, 26 NaHCO₃, 1.23 NaH₂PO₄, 10 MgSO₄, 0.5 CaCl₂, and 10 dextrose

Slice recovery conditions

1 h submerged

1 h submerged

1 h ns

DREADD agonist

DREADD agonist

CNO

CNO

CNO

Concentration

10 µM

10 µM

ns

Duration of CNO application

25 min

25 min

10 min

Slice electrophysiology recording conditions

Stimulation frequency

0.033 Hz

0.017 Hz

0.07 Hz

Stimulations during baseline

30 min (60 stimulations)

10 min (10 stimulations)

10 min (40 stimulations)

Pause in stimulation

Yes

Yes

No

Stimulations necessary for induction of synaptic potentiation

Gq-DREADD: 21

Gi-DREADD: 1

Gq-DREADD: 1 (1 mM Mg²⁺)

21 (2 mM Mg²⁺)

Gi-DREADD: 40+ additional 40 Hz stimulus

Bath temperature

28 °C

32 °C

28–30 °C

aCSF composition (in mM)

124 NaCl, 3 KCl, 26 NaHCO₃, 1.4 NaH₂PO₄, 1 MgSO₄, 2 CaCl₂ and 10 glucose

126 NaCl, 2.6 KCl, 26 NaHCO₃, 1.25 NaH₂PO₄, 1 MgCl₂, 2 CaCl₂ and 10 glucose

124 NaCl, 5 KCl, 26 NaHCO₃, 1.23 NaH₂PO₄, 1 MgSO₄, 2 CaCl₂ and 10 dextrose