Abstract
Abstract— It has been shown previously that pineal composition and some of its enzyme activities in mammals appear to be responsive to light and darkness in vivo, possibly indirectly. One such possible indirect mechanism would be by whole animal activity and the sympathetic innervation of the pineal. Study of the rhythmic changes in the pineal ethanol‐soluble fraction (mostly lipid) and in whole animal running activity in normal, adult male rats in standard daily photocycle and then in continuous light, shows rapid dissociation of the two rhythms in continuous light, with pineal composition being more light‐dependent.The free‐running circadian rhythm in the male rat's running activity in both standard daily photocycle and continuous light is shown to be similar in normal and in pinealectomized animals. This negative finding is relevant with regard to an hypothesized pineal function in lower tetrapods in regulation of locomotor activity in response to solar radiation.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
