Dorsal premammillary nucleus differentially modulates defensive behaviors induced by different threat stimuli in rats

D. Caroline Blanchard, Chun I. Li, David Hubbard, Chris M. Markham, Mu Yang, Lorey K. Takahashi, Robert J. Blanchard

Research output: Contribution to journalArticle

71 Scopus citations

Abstract

Lesions of the dorsal premammillary nucleus (PMd) have been reported to produce dramatic reductions in responsivity of rats to a live cat. Such lesions provide a means of analyzing the potentially differential neural systems involved in different defensive behaviors, and the relationship between these systems and concepts such as anxiety. Rats with bilateral electrolytic lesions of the PMd were run in an elevated plus maze (EPM), exposed first to cat odor and then to a live cat, and assessed for postshock freezing and locomotion. PMd lesions produced a dramatic reduction in freezing, avoidance, and stretch attend to the cat odor stimulus, and reduction in freezing, with greater activity, and enhanced stretch approach to cat exposure. However, PMd lesions had minimal effects in the EPM, and postshock freezing scores were unchanged. These results confirm earlier findings of reduced defensiveness of PMd-lesioned rats to a cat, extending the pattern of reduced defensiveness to cat odor stimuli as well, but also suggest that such lesions have few effects on nonolfactory threat stimuli.

Original languageEnglish (US)
Pages (from-to)145-148
Number of pages4
JournalNeuroscience Letters
Volume345
Issue number3
DOIs
StatePublished - Jul 24 2003
Externally publishedYes

    Fingerprint

Keywords

  • Cat exposure
  • Cat odor
  • Defensive behavior
  • Dorsal premammillary nucleus
  • Elevated plus maze
  • Emotion
  • Freezing
  • Rat

ASJC Scopus subject areas

  • Neuroscience(all)

Cite this

Blanchard, D. C., Li, C. I., Hubbard, D., Markham, C. M., Yang, M., Takahashi, L. K., & Blanchard, R. J. (2003). Dorsal premammillary nucleus differentially modulates defensive behaviors induced by different threat stimuli in rats. Neuroscience Letters, 345(3), 145-148. https://doi.org/10.1016/S0304-3940(03)00415-4