Cerebroventricular administration of interferon-gamma modifies locomotor activity in the golden hamster.
The present study was undertaken to examine whether the intracerebroventricular (i.c.v.) administration of interferon (IFN)-gamma could modify 24-hour wheel running locomotor activity in the golden hamster. Hamsters implanted with a cannula in the third ventricle received a single i.c.v. injection of 1 microl of murine recombinant IFN-gamma (40 IU/microl) or its vehicle (saline) at ZT 6 or ZT 18 (with ZT 12 defined arbitrarily as the time of lights off) and their activities were monitored during 24 h. The i.c.v. administration of IFN-gamma at ZT 6 produced a significant phase advance in acrophase of rhythm, an effect not seen at ZT 18. Also, IFN-gamma depressed mesor value significantly, the effect was seen at both times. These results clearly showed that the circadian clock could be modified by IFN-gamma microinjections. One explanation could be the presence of IFN-gamma receptor in the rat suprachiasmatic nucleus, supporting a direct effect on the central oscillator. However, another hypothesis could not be ruled out.
Boggio
Verónica I
VI
Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.
Castrillón
Patricia O
PO
Perez Lloret
Santiago
S
Riccio
Patricia
P
Esquifino
Ana I
AI
Cardinali
Daniel P
DP
Cutrera
Rodolfo A
RA
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D001522:Behavior, Animal / Q000187:drug effects*; D002940:Circadian Rhythm / Q000187:drug effects*; D006224:Cricetinae; D007276:Injections, Intraventricular; D007371:Interferon-gamma / Q000494:pharmacology*; D008297:Male; D008647:Mesocricetus; D009043:Motor Activity / Q000187:drug effects*; D013493:Suprachiasmatic Nucleus / Q000502:physiology
D000970:Antineoplastic Agents; D007371:Interferon-gamma