Table 1.

Summary of experimental groups of DBA/1 mice

Experiments	Experimental groups	Number of mice
Photostimulation (9 mW, ChR2+)	1-min PS	8*
	5-min PS	6*
	10-min PS	6*
	15-min PS	15*
Photostimulation (15 mW, ChR2+)	3-min PS	4*
	5-min PS	6*
Photostimulation (9 or 15 mW, ChR2−)	15- or 5-min PS	6
Photostimulation (9 mW, 5-HTP)	10-min PS	6*
	vehicle or 5-HTP
Photostimulation (9 mW, OND)	15-min PS	6*
	vehicle or OND
Photostimulation (9 mW, PTZ)	PTZ only	6
	PTZ with 15-min PS	6
Injection (i.p.)	Vehicle or 5-HTP	8*
Injection (i.p.)	Vehicle or OND	6*
Immunohistochemistry	ChR2-TPH2	3
Immunohistochemistry	ChR2-c-fos with PS	3
	ChR2-c-fos without PS	3

PS, photostimulation; 5-HTP, 5-hydroxytryptophan; OND, ondansetron; PTZ, pentylenetetrazole.

^*indicates that pre-treatment control or vehicle was performed in the same group of mice as treatment.