Serotonin 5-HT2 and 5-HT1A receptors in the periaqueductal gray matter differentially modulate tonic immobility in guinea pig

Pro‐inflammatory cytokines, IL‐1β and TNF‐α, produce persistent compromise in tonic immobility defensive behaviour in endotoxemia guinea‐pigs

“…On the other hand, the agonists of GABA‐A and 5‐HT 2 receptors into the ventrolateral portion reduced the duration of TI (Monassi et al . , , Monassi & Menescal‐de‐Oliveira ). The neuronal activation into PAG may be induced by a series of stimuli, such as acute stress, inflammation and TI episodes (Sugama et al .…”

μ1- and 5-HT1-dependent mechanisms in the anterior pretectal nucleus mediate the antinociceptive effects of retrosplenial cortex stimulation in rats

“…In contrast, neither the injection of atropine (a cholinergic muscarinic receptor antagonist) nor ketanserine (a 5-HT 2 receptor antagonist) into the dAPtN or vAPtN were effective against SPA from the RSC in tail flick or incision pain tests, respectively. It should be noted that atropine (Villarreal and Prado, 2007) and ketanserine (Monassi and Menescal-de-Oliveira, 2004) were used at Fig. 4.…”

Comparative analysis of the mechanisms of attack and defense among higher brain animals

“…An increasing body of data further suggests that the serotonergic system also plays a principal role in the regulation of attack and defense [49][50][51][52][53]. It has been shown that 5-HT exerts an inhibitory influence on defensive forms of aggression through the activation of 5-HT 1A receptors [54,55]. However, activation of the 5-HT 2 receptor in the midbrain PAG potentiates defensive rage behavior [56].…”