Effects of corticotropin-releasing factor (CRF) and opiates on amphibian locomotion

Christopher A. Lowry, Pierre Deviche, Frank L. Moore

Research output: Contribution to journalArticlepeer-review

39 Scopus citations


Male rough-skinned newts (Taricha granulosa) were used as a model for the study of the neuroendocrine regulation of locomotion. Intracerebroventricular (i.c.v.) injections of nanogram quantities of corticotropin-releasing factor (CRF) dose-dependently increased locomotion as measured in a circular open-field test arena. In other studies animals received intraperitoneal (i.p.) injections of saline or naloxone, a synthetic opioid antagonist, followed by i.c.v. injections of saline or CRF. With 1-min intervals between injections, neither i.p. saline nor naloxone injections modified the stimulatory effects of CRF injections on locomotor activity. In contrast, with 20-min intervals between injections, the naloxone-plus-CRF injected newts displayed more locomotor activity than the saline-plus-CRF injected newts, suggesting that the opioid system modulated the behavioral effects of CRF. An i.p. injection of bremazocine, an opiate κ-receptor agonist, suppressed spontaneous locomotion but not CRF-induced locomotion. In contrast, an i.p. injection of morphine, an opiate μ-receptor agonist, did not affect spontaneous locomotion but reduced CRF-induced locomotion, indicating further that the opioid system may modulate the behavioral effects of CRF in this amphibian. The present study provides the first evidence that both CRF and opioids may be involved in the regulation of amphibian locomotor activity.

Original languageEnglish (US)
Pages (from-to)94-100
Number of pages7
JournalBrain Research
Issue number1
StatePublished - Apr 9 1990
Externally publishedYes


  • Amphibian
  • Bremazocine
  • Corticotropin-releasing factor
  • Locomotion
  • Morphine
  • Naloxone
  • Opiate

ASJC Scopus subject areas

  • General Neuroscience
  • Molecular Biology
  • Clinical Neurology
  • Developmental Biology


Dive into the research topics of 'Effects of corticotropin-releasing factor (CRF) and opiates on amphibian locomotion'. Together they form a unique fingerprint.

Cite this