Involvement of septal and striatal dopamine D-2 receptors in yawning behavior in rats

Abstract

A behavioral study was performed in an attempt to understand the neuronal mechanisms involved in yawning behavior in rats. Subcutaneous injections of low doses of apomorphine (0.05-0.25 mg/kg) or piribedil (0.2-1.0 mg/kg), which preferentially activate presynaptic dopamine autoreceptors at those doses, evoked yawning. Marked yawning responses were also elicited by both 3-PPP (5-20 mg/kg, SC) and TL-99 (1-2 mg/kg, SC). SK & F 38393, a dopamine D-1 receptor agonist, at doses ranging from 0.1 to 8.0 mg/kg (SC) induced neither yawning nor stereotypy. However, bromocriptine (0.5-32.0 mg/kg, SC), a dopamine D-2 receptor agonist, induced yawning for which the dose-response curves showed a bell-shaped form. After a higher dose of 32 mg/kg (SC) bromocriptine, some rats occasionally showed sniffing and sawdust chewing. Yawning responses induced by systemic injection of apomorphine, piribedil, 3-PPP or bromocriptine were wholly suppressed after treatment with sulpiride (10 mg/kg SC), a dopamine D-2 receptor antagonist. Bilateral injections of apomorphine (20 micrograms/side X 2), piribedil (100 micrograms/side X 2) or 3-PPP (50, 100 micrograms/side X 2) into the striatum or septum also elicited marked yawning. The results indicate that low doses of apomorphine, piribedil, 3-PPP, TL-99 or bromocriptine elicit yawning by stimulating dopamine D-2 receptors and striatal and septal dopaminergic systems may be related to the occurrence of yawning behavior.

Food Restriction Alters N′-Propyl-4,5,6,7-tetrahydrobenzothiazole-2,6-diamine dihydrochloride (Pramipexole)-Induced Yawning, Hypothermia, and Locomotor Activity in Rats: Evidence for Sensitization of Dopamine D2 Receptor-Mediated Effects

“…Interpretation of changes in D2/D3 agonist-induced locomotor activity is further complicated by the fact that D2-like antagonists often alter locomotor activity on their own. In addition to their effects on locomotor activity, D2/D3 agonists are known to possess a variety of other behavioral effects including the induction of yawning (Yamada et al, 1986), penile erection (PE) (Melis et al, 1987), and hypothermia (Faunt and Crocker, 1987). Although postsynaptic D2/D3 receptors within the mesolimbic dopaminergic pathway are thought to mediate the locomotor effects of D2-like agonists (Levant, 1997), the induction of yawning and PE by D2-like agonists is thought to be mediated by postsynaptic D2-like receptors on oxytocinergic neurons in the paraventricular nucleus (Argiolas and Melis, 1998).…”

Inhibitory effect of morphine on yawning induced by cholinoceptor and dopamine D2 receptor activation in rats

“…It has been proposed that yawning induced by low doses of dopamine receptor agonists is due to activation of D2 receptors (Yamada et al, 1986;Zarrindast & Poursoltan, 1989), although D1 receptors may be involved in yawning induced by apomorphine (Morelli et al, 1986). The yawning induced by dopamine agonists appears to be mediated via a cholinergic mechanism, since it is inhibited by muscarinic receptor blockade (Mogilnicka et al, 1984;Yamada et al, 1986;Zarrindast & Poursoltan, 1989).…”

“…These studies suggest that dopamine receptor agonists induce yawning by activation of the cholinergic system (Carlsson, 1975;Di-Chiara et al, 1976). Links between acetylcholine and dopaminergic neurones have been described in the septor hippocampal system and the striatum (Guyenet et al, 1974;Agid et al, 1975;Storm-Mathisen, 1977) and it has been shown that stimulation and lesion of these structures affect yawning (Jakobartl & Huston, 1977;Dourish & Huston, 1985;Yamada et al, 1986;Stoessl et al, 1987;Laping & Ramirez, 1988). It has also been suggested that dopamine agonists elicit yawning by stimulating dopamine D2 receptors within these structures (Yamada et al, 1986 (Pollard et al, 1977).…”

“…Links between acetylcholine and dopaminergic neurones have been described in the septor hippocampal system and the striatum (Guyenet et al, 1974;Agid et al, 1975;Storm-Mathisen, 1977) and it has been shown that stimulation and lesion of these structures affect yawning (Jakobartl & Huston, 1977;Dourish & Huston, 1985;Yamada et al, 1986;Stoessl et al, 1987;Laping & Ramirez, 1988). It has also been suggested that dopamine agonists elicit yawning by stimulating dopamine D2 receptors within these structures (Yamada et al, 1986 (Pollard et al, 1977). Morphine, methadone and other opiates modulate dopaminergic neurotransmission in mesolimbic (Wood, 1983;Iyenger et al, 1987), mesocortical (Kim et al, 1986) and nigrostriatal (Ahtee & Kaariainen, 1973;Gauchy et al, 1973;Costa et al, 1975;Wood et al, 1980) projections.…”

Effects of Lead Exposure on Licking and Yawning Behaviour in Rats

“…The involvement of central cholinergic (UrbaHolmgren et al 1977;Yamada & Furukawa 1980;Ushijima et al 1984;Zarrindast & Poursoltan 1989) and dopaminergic systems (Mogilnicka & Klimek 1977;Baggio & Ferrari 1983;Zarrindast & Poursoltan 1989) in yawning behaviour has been established. Septa1 and striatal dopamine receptors have been proposed to be involved in yawning behaviour in rats (Yamada et al 1986). The behaviour seems to be mediated through D2 dopamine receptor in rats (Protais et al 1983;Gower et al 1984;Longoni et al 1987;Zarrindast & Poursoltan 1989).…”