Altered neuronal sensitivity of lateral geniculate neurones to noradrenaline and 5-HT following exposure to continuous lighting.
Rats were housed in either continuous lighting (LL), an extended photoperiod of 18 h light-6 h dark (LD 18:6) or a 12 h light-12 h dark (LD 12:12) lighting cycle. The effects of these various lighting regimens on the sensitivity of dorsal lateral geniculate neurones to iontophoresed noradrenaline and serotonin (5-HT) was examined. Exposure to either continuous lighting or to an extended photoperiod (LD 18:6) resulted in the development of an enhanced responsiveness to iontophoresed noradrenaline (alpha 1-adrenoceptor) and 5-HT. The development of light-induced noradrenaline and 5-HT supersensitivity resembles the changes obtained with antidepressant treatments.
Mason
R
R
Department of Physiology and Pharmacology, Medical School, Queen's Medical Centre, Nottingham, U.K.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D005829:Geniculate Bodies / Q000187:drug effects / Q000502:physiology*; D008029:Lighting; D009638:Norepinephrine / Q000494:pharmacology*; D010775:Photic Stimulation; D051381:Rats; D012701:Serotonin / Q000494:pharmacology*; D014795:Visual Pathways / Q000502:physiology
D012701:Serotonin; D009638:Norepinephrine