Oxytocin and vasopressin hexapeptide fragments have opposing influences on conditioned freezing behavior.
We investigated the influence of C-terminal fragments of oxytocin (OT) and arginine vasopressin (AVP) on conditioned freezing behavior. Subcutaneous injections of 0.3 microgram AVP(4-9) or OT(4-9) given to rats after shock training or before behavioral observation significantly altered fear-induced freezing behavior. Animals treated with OT hexapeptide froze less than controls, while animals treated with AVP hexapeptide froze more. These results support the concept that the hexapeptide metabolites of oxytocin and vasopressin can selectively modulate certain behavioral processes, and that these peptides have opposite effects on performance in behavioral tests designed to evaluate memory consolidation and retrieval.
Stoehr
J D
JD
Department of Physiology, Dartmouth Medical School, Hanover, NH 03756.
Cramer
C P
CP
North
W G
WG
D000818:Animals; D001127:Arginine Vasopressin / Q000494:pharmacology* / Q000502:physiology; D001143:Arousal / Q000187:drug effects* / Q000502:physiology; D003214:Conditioning, Classical / Q000187:drug effects* / Q000502:physiology; D005239:Fear / Q000187:drug effects* / Q000502:physiology; D005260:Female; D011939:Mental Recall / Q000187:drug effects* / Q000502:physiology; D009043:Motor Activity / Q000187:drug effects* / Q000502:physiology; D010121:Oxytocin / Q000494:pharmacology* / Q000502:physiology; D010446:Peptide Fragments / Q000494:pharmacology*; D051381:Rats; D013045:Species Specificity
D010446:Peptide Fragments; D001127:Arginine Vasopressin; D010121:Oxytocin; C045881:argipressin (4-9)