Author/Editor     Lerchl, Alexander; Niehaus, Michael
Title     Investigations on direct effects of 50HZ magnetic fields on hamster pineal gland melatonin production
Type     članek
Source     In: Hočevar A, Črepinšek Z, Kajfež-Bogataj L, editors. Biometeorology 14. Proceedings of the 14th international congress of biometeorology. Part 2. (Vol 3); 1996 Sep 1-8; Ljubljana. Ljubljana: Slovenian meteorological society,
Publication year     1996
Volume     str. 495-503
Language     eng
Abstract     Several studies addressing the biological effects of weak magnetic fields (MF) have indicated that the pineal glands of mammals may respond with a decreased production of melatonin, the gland's primary hormone. However, the site of actions of such MFs has not yet been superfusion system for pineal glands from adult Djungarian hamsters (Phodopus sungorus). After sacrifice, the glands were quickly removed and transferred to chambers, consisting of round glass tubes, closed with rubber stoppers. Oxygenated Krebs-Ringer buffer at a physiological pH was pumped at a flow rate of 0.4 ml min-1 through the chambers. Piheal glands were stimulated for 30 minutes with a beta-adrenergic agonist (isoproterenol) for stimulating melatonin production. Three groups of 8 glands in individual chambers each were surrounded by Helmhotz coils and either sham exposed, or exposed throughout the whole experiment to 50 Hz sine wave MF, or 50 Hz rectangular MF, respictively. The allocation of the generators to the coils was done in a blind fashion. A total of three experiments at flux densities of 86 micro Tesla, and 0.86 micro Testa, respectively, were performed. In none of these experiments, exposed pineal glands differed from sham exposed controls in terms of melatonin production. It is concluded that the effects of MFs on melatonin production are not mediated through direct effects on the pineal glands, at least with respect to a pure beta-adrenergic stimulation. It appears more likely that either the eyes, or parts of the neural innervation are involved in the effects of MFs on melatonin synthesis.
Descriptors     PINEAL BODY
MELATONIN
ELECTROMAGNETIC FIELDS
HAMSTERS
ISOPROTERENOL