Serotonin stimulates gonadotropin release in female and male goldfish, Carassius auratus L

Gen Comp Endocrinol. 1988 Dec;72(3):374-82. doi: 10.1016/0016-6480(88)90159-1.


Effects of serotonin (5-HT) on serum gonadotropin (GtH) levels were studied in female and male goldfish, Carassius auratus L. Intraperintoneal (ip) administration of 5-HT (10 micrograms/g) produced a significant increase in serum levels of GtH at 0.5, 1, and 2 hr but not at 3-4 hours, after the drug was injected. Administration of different concentrations of 5-HT into the brain third ventricle (iv) did not affect serum GtH levels. In both sexes, the intraperitoneal administration of different doses of 5-HT (2.5-20 micrograms/g) caused a dose-dependent increase in serum GtH levels in fish at different gonadal stages; the greatest responses occurred in mature (= prespawning) fish. Fluoxetine (10 micrograms/g; ip), a 5-HT reuptake inhibitor, potentiated the stimulatory effects of 5-HT on GtH secretion. Ketanserin (10 micrograms/g; ip), a 5-HT antagonist, did not modify basal GtH levels; however, ketanserin blocked the 5-HT induced release of GtH. These results indicate that 5-HT has a stimulatory effect on GtH release in goldfish, most likely at the level of the pituitary gland.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dose-Response Relationship, Drug
  • Fluoxetine / administration & dosage
  • Goldfish
  • Gonadotropins / blood*
  • Gonadotropins / metabolism
  • Injections, Intraperitoneal
  • Ketanserin / administration & dosage
  • Seasons
  • Serotonin / administration & dosage*
  • Time Factors


  • Gonadotropins
  • Fluoxetine
  • Serotonin
  • Ketanserin