title: Effects of apomorphine, clonidine or 5-methoxy-NN-dimethyltryptamine on approach and escape components of lateral hypothalamic and mesencephalic central gray stimulation in two inbred strains of mice.
abstract: The effects of intraperitoneal injections of increasing doses of apomorphine, clonidine or 5-methoxy-NN-dimethyltryptamine (5-m-DMT) on approach and escape reactions induced by lateral hypothalamic (LH) or mesencephalic central gray (CG) stimulation were compared in BALB/c and DBA/2 mice. Apomorphine increased both the approach latency for LH stimulation and the escape latency for CG stimulation; the BALB/c strain was more reactive than DBA/2 animals. Clonidine reduced the approach latency for LH stimulation only in the BALB/c strain. 5-m-DMT increased escape latency both for LH and CG stimulation only in the DBA/2 strain. These results suggest that the neurochemical regulation of escape reactions respectively generated by LH or CG activation is partially different: dopamine seems to be involved only in CG aversion, whereas serotonin (5-HT) modulates both LH and CG escape reactions. Moreover, our results demonstrate a noradrenergic influence on the appetitive component of LH stimulation. Finally, they confirm that approach and escape reactions, particularly when induced from lateral hypothalamus, depend on distinct neuronal populations.
mesh_terms: D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D001066:Appetite / Q000187:drug effects*; D003000:Clonidine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004924:Escape Reaction / Q000187:drug effects*; D007026:Hypothalamic Area, Lateral / Q000187:drug effects / Q000502:physiology*; D008297:Male; D008636:Mesencephalon / Q000187:drug effects / Q000502:physiology*; D008732:Methoxydimethyltryptamines / Q000494:pharmacology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008811:Mice, Inbred DBA; D012701:Serotonin / Q000031:analogs & derivatives*; D013238:Stereotaxic Techniques
chemical_list: D008732:Methoxydimethyltryptamines; D012701:Serotonin; D003000:Clonidine; D001058:Apomorphine