Pineal 'synaptic ribbons' and serum melatonin levels in the rat following the pulse action of 52-Gs (50-Hz) magnetic fields: an evolutive analysis over 21 days.

In continuation of earlier studies, we have investigated the influence of 52-Gs (50-Hz) magnetic fields on the evolution of pinealocyte 'synaptic ribbons' and serum melatonin levels in rats, following 30 min daily exposure. The animals were sacrificed after 1, 3, 7, 15 and 21 days. A significant decrease in the number of synaptic ribbons was observed after 15 and 21 days, together with a significant drop in serum melatonin concentrations after 15 days. The mediating role of the retina in these modifications and magnetic field effects is discussed.

Morphometric and structural study of the pineal gland of the Wistar rat subjected to the pulse action of a 52 Gauss, (50 Hz) magnetic field. Evolutive analysis over 21 days.

A study is made of the pinealocyte karyometric index and pineal gland ultrastructure in 60 male Wistar rats (250 g on average) sacrificed 1, 3, 7, 15 and 21 days after commencing application of a magnetic field (intensity, 52 Gauss; frequency, 50 Hz) for a period of 30 minutes daily. A progressive decrease was observed in karyometric index corresponding to both the peripheral and central gland region, with a significant difference between the two after 3 and 7 days (p less than 0.0001). A significant increase in lipid activity was also seen during the same period. Pineal gland structural organization during the experimental period is evaluated at both light and electron microscope level.