Avtor/Urednik		Hawlina, M; Ikeda, H
Naslov		The role of melatonin and dopamine in retinal renewal and degeneration
Tip		članek
Vir		Zdrav Vestn
Vol. in št.		Letnik 62, št. Suppl 1
Leto izdaje		1993
Obseg		str. 23-31
Jezik		eng
Abstrakt		The outer segments of the photoreceptors of the retina are renewed daily by the phagocytosis of discarded outermost discs by the retinal pigment epithelium, whilst new discs are being formed at the inner segments. This process is regulated by retinal melatonin and dopamine. Derangement in phagocytosis by the retinalpigment epithelium causes retinal degeneration in one ofthe most studied animal model of retinitis pigmentosa, the RCS rat. Similar mechanisms are also proposed as a possible cause of some other clinical conditions, such as Best's vitelliform dystrophy and some drug related retinopathies. This paper reviews studies on photoreceptor renewal process with emphasis on the role of melatonin and dopamine. It also presents our work on the electroretinography which reflects the diurnal rhythmicity of the photoreceptor renewal process. Abnormally high level of retinal melatonin content that we found in RCS rats is discussed as a possible causative factor of degeneration. Finally, our results from electroretinography after long-term application of a dopamine D2 agonist, bromocriptine, are presented in an attempt of therapeutic approach to this type of retinal degeneration.
Deskriptorji		DOPAMINE MELATONIN RETINAL DEGENERATION RATS, INBRED STRAINS CIRCADIAN RHYTHM ELECTRORETINOGRAPHY RETINA PHAGOCYTOSIS