Effects of general anaesthetics on 5-HT neuronal activity in the dorsal raphe nucleus

► Pentobarbitone selectively enhanced GABAA response. ► Ketamine attenuated NMDA response, decreased α1 adrenoceptor driven basal firing and enhanced GABAA and 5-HT1A responses. ► Chloral hydrate attenuated NMDA response and enhanced GABAA and 5-HT1A responses. ► Urethane attenuated NMDA response, increased basal firing, and increased GABAA response.