title: Effects of cocaine-amphetamine regulated transcript (CART) on hormone release.
abstract: OBJECTIVE
  Cocaine- and amphetamine-regulated transcript (CART) is a recently described neuropeptide widely expressed in the rat brain. CART is abundant in hypothalamus nuclei controlling anterior pituitary function. In the paraventricular nucleus CART mRNA is colocalized with vasopressin and corticotrophin-releasing factor containing neurons. The data may suggest that CART plays a role in hypothalamic regulation of neuroenocrine functions.
  
  
  METHODS
  Male Wistar-Kyoto rats were investigated. Experiment I: CART was administered intracerebroventricularly (i.c.v.) in a dose of 0.5 microg dissolved in 5 microl vehicle. At 60, 120 min after the infusion of CART or vehicle animals were decapitated and trunk blood was collected until hormonal estimations. Experiment II: CART in a dose of 10 microg was injected intravenously (i.v.). At 60, 120, 240 min the rats were decapitated and the trunk blood was collected. Serum rLH, rFSH, rPRL, rTSH, rGH and plasma leptin, NPY concentrations were measured by RIA methods.
  
  
  RESULTS
  CART administered centrally (i.c.v.) simulated significantly GH release after 60 min (p<0.05) and after 120 min (p<0.01). CART increased also PRL after 60 min (p<0.05). A marked increase of corticosterone level was observed at 60 and 120 min (p<0.01, p<0.01). We did not observe significant changes in LH, FSH and TSH. We found an increase of serum leptin concentrations at 60 min after CART administration (p<0.01). However, serum NPY levels did not change. After intravenous injection (i.v.) of CART an increase of GH was observed at 120, 240 min (p<0.01, p<0.01, respectively). A rise in serum PRL was found at 240 min (p<0.05). Corticosterone concentrations were enhanced at 60, 120, 240 min (p<0.01, p<0.01, p<0.01, respectively). We did not observe significant changes in LH, FSH and TSH.
  
  
  CONCLUSIONS
  CART may play a modulating role in the mechanism of pituitary hormone release.
authors.affiliation: Neuroendocrinology Department, Medical Centre of Postgraduate Education, Bogusława Baranowska, Marymoncka 99, 01-813 Warsaw, Poland. zncmkp@polbox.com
authors.forename: Bogusława
authors.initials: B
authors.lastname: Baranowska
authors.forename: Ewa
authors.initials: E
authors.lastname: Wolińska-Witort
authors.forename: Lidia
authors.initials: L
authors.lastname: Martyńska
authors.forename: Magdalena
authors.initials: M
authors.lastname: Chmielowska
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Baranowska-Bik
mesh_terms: D000818:Animals; D003345:Corticosterone / Q000097:blood / Q000378:metabolism; D006728:Hormones / Q000097:blood* / Q000378:metabolism*; D007276:Injections, Intraventricular; D020738:Leptin / Q000097:blood / Q000378:metabolism; D008297:Male; D009419:Nerve Tissue Proteins / Q000008:administration & dosage / Q000494:pharmacology*; D009478:Neuropeptide Y / Q000097:blood / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein
chemical_list: D006728:Hormones; D020738:Leptin; D009419:Nerve Tissue Proteins; D009478:Neuropeptide Y; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein; D003345:Corticosterone