Neurobiologic effects of bright artificial light.
Bright light is an effective treatment of winter depression. Study of the effects of this treatment on mechanisms thought to be involved in the pathophysiology of depressive disorders is reviewed. Measurement of a physiological parameter, namely the change in core temperature using an intraperitoneally implanted radio transmitter sensitive to temperature in freely moving rats, indicates that treatment with bright light under various experimental conditions tends to powerfully subsensitize muscarinic and nicotinic mechanisms. Pulses of bright light during the phase delay portions of the PRC blunt sensitivity to clonidine. Our studies with bright light are consistent with those indicating that heterocyclic antidepressants and a monoamine oxidase inhibitor produce subsensitivity to the thermic effects of nicotine. Reports of the influences of full-spectrum bright light and its impact on targeted neurotransmitter mechanisms call attention to the anatomical substratum mediating its effects. Possible receptor changes are measurable using receptor binding techniques and quantitative autoradiography. The physiological effects of this interesting treatment raises questions of its impact on coupling mechanisms and second messengers.
Dilsaver
S C
SC
Psychopharmacology Program, Ohio State University, Columbus 43210-1228.
D000639:Amitriptyline / Q000494:pharmacology; D000818:Animals; D000928:Antidepressive Agents / Q000494:pharmacology*; D001921:Brain / Q000187:drug effects / Q000502:physiology*; D003000:Clonidine / Q000494:pharmacology; D003624:Darkness; D003866:Depressive Disorder / Q000628:therapy*; D006801:Humans; D008027:Light; D008029:Lighting; D009538:Nicotine / Q000494:pharmacology; D010095:Oxotremorine / Q000494:pharmacology; D010789:Phototherapy; D051381:Rats; D012016:Reference Values; D013315:Stress, Psychological
D000928:Antidepressive Agents; D000639:Amitriptyline; D010095:Oxotremorine; D009538:Nicotine; D003000:Clonidine