Opioid receptors in the prelimbic cortex modulate restraint stress-induced cardiovascular responses in the rat

Autor(es)

Fassini, Aline ^[1] ; Scopinho, America A. ^[1] ; Resstel, Leonardo B. M. ^[1] ; Correa, Fernando M. A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sch Med Ribeirao Preto, Dept Pharmacol, BR-14049 Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Neuropharmacology; v. 85, p. 367-374, OCT 2014.
• Citações Web of Science: 6

Resumo

The prelimbic cortex (PL) is involved in the control of behavioral and autonomic responses to stress. The present study aimed to investigate whether opioid neurotransmission in the PL modulates autonomic responses evoked by restraint stress (RS). Bilateral microinjection of 0.03, 0.3 and 3 nmol/100 nL of the nonselective opioid antagonist naloxone into the PL reduced pressure and tachycardiac responses evoked by RS. However, no effects were observed after its injection at doses of 0.003 and 30 nmol/100 nL, thus resulting in an inverted U-shaped dose-inhibition curve. Similar to naloxone, the selective mu-opioid antagonist CTAP, and the selective mu-opioid antagonist nor-BNI, also reduced MAP and HR increases induced by RS when injected into the PL, whereas treatment with the selective delta-opioid antagonist naltrindole did not affect the pressor and tachycardiac response caused by RS. Blockade of opioid neurotransmission in the PL did not affect the fall in tail temperature and increase in body temperature induced by RS. The present results confirm the involvement of PL opioid neurotransmission in the modulation of cardiovascular responses evoked during the exposure to an aversive situation, and suggest that responses observed after the blockade of local opioid receptors is due to alterations in PL neuronal activity. Furthermore, these results suggest that a distinct circuitry is involved in modulation of the sympathetic output to different vascular territories. (C) 2014 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 12/17626-7 - Mecanismos celulares e moleculares envolvidos no papel de neurotransmissores atípicos em transtornos neuropsiquiátricos
• Beneficiário: Francisco Silveira Guimaraes
• Linha de fomento: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/00249-9 - Envolvimento da neurotransmissão opioidérgica da amígdala medial na mediação das respostas autonômicas e hormonais causadas pelo estresse de restrição em ratos
• Beneficiário: Aline Fassini
• Linha de fomento: Bolsas no Brasil - Doutorado
• Processo FAPESP: 12/09300-4 - O sistema noradrenérgico presente no núcleo leito da estria terminal modula a resposta emocional condicionada contextual: uma possível interação com o CRF e as neurotransmissões glutamatérgica e nitrérgica
• Beneficiário: Leonardo Resstel Barbosa Moraes
• Linha de fomento: Auxílio à Pesquisa - Regular