la melanopsina e la nascita

Germana Zaccagnini segnala che, dopo aver letto sul blog l'articolo:

«marketpress.info
GLI SCIENZIATI BRITANNICI SCOPRONO COME RENDERE LE CELLULE OCULARI SENSIBILI ALLA LUCE»
(pubblicato sul blog in data 2.2)

ha fatto una ricerca sulla melanopsina, la molecola di cui si parla nell'articolo, utilizzando il sito di pubblicazioni scientifiche www.pubmed.com
Quanto segue è l'abstract di un articolo che ha trovato e che sembra interessante, parrebbe infatti che la melanopsina sia un fotopigmento che risponde alla luce dalla nascita.

Neuroreport. 2004 Oct 25;15(15):2317-20.
Melanopsin containing retinal ganglion cells are light responsive from birth.
Hannibal J, Fahrenkrug J.
Department of Clinical Biochemistry, Bispebjerg Hospital, University of Copenhagen, Bispebjerg Bakke 23, DK-2400 Copenhagen NV, Denmark.

Photoentrainment of the biological clock located in the suprachiasmatic nucleus (SCN) begins shortly after birth. Here we show using c-FOS immunoreactivity as a marker for neuronal activity that the melanopsin/PACAP containing retinal ganglion cells (RGCs) which project to the SCN as the retinohypothalamic tract (RHT) are responsive to light from birth. After postnatal day 12 where the classical photoreceptors become functional other RGCs and cells of the inner nuclear cell layer also respond to light. Light also induces c-FOS immunoreactivity in the retinorecipient SCN from the first postnatal day and accordingly PACAP immunoreactive fibres are visible in the SCN. The results indicate that the retina is light responsive before functional rods and cones and that the RHT is functional from birth supporting that photoentrainment of the biological clock begins shortly after birth.