Effects of 50 Hz extremely low frequency magnetic field on the morphology and function of boar spermatozoa capacitated in vitro N. Bernabo ` a , E. Tettamanti b , M.G. Pistilli a , D. Nardinocchi c , P. Berardinelli c , M. Mattioli a , B. Barboni a, * a Institute of Physiology, Department of Biomedical Science, P.zza Aldo Moro 45, Teramo, Italy b Institute for Radiological Research, Department of Biomedical Science, P.zza Aldo Moro 45, Teramo, Italy c Institute of Cytology, Department of Biomedical Science, P.zza Aldo Moro 45, Teramo, Italy Received 13 March 2006; received in revised form 3 October 2006; accepted 4 October 2006 Abstract The aim of this study was to evaluate the effect of an acute exposure to a sinusoidal MF-ELF (50 Hz, 1 mT) on the ability of boar mature spermatozoa to acquire the fertilizing competence in vitro. The spermatozoa exposed during the 4 h of incubation to the MF- ELF were evaluated for morphological (surface morphology and acrosome integrity) and functional parameters (cell viability, motility, induction of acrosomal reaction, AR, and the ability to in vitro fertilize oocytes). In parallel, the intracellular Ca 2+ levels as well as the major mechanisms of Ca 2+ clearance were assessed: 45 Ca intakes and intracellular Ca 2+ sequestration by analyzing intracellular Ca 2+ elevation induced by thapsigargin or studying mitochondrial function with Mito-Tracker. The MF-ELF exposure did not affect sperm viability and morphology during the first h of incubation when sperm Ca 2+ homeostasis were already compromised. First of all, MF-ELF treated spermatozoa showed resting intracellular Ca 2+ levels significantly lower than those recorded in controls. This result was dependent on a lower extracellular Ca 2+ intake and from the inhibitory role exerted on both intracellular Ca 2+ storages. As a consequence, after 1 h of incubation MF-ELF exposed cells displayed a reduced motility, a modest reactivity when coincubated with solubilized zonae pellucidae and a reduction in oocyte penetrating ability. After 2 or 4 h of incubation, in addition, signs of morphological damage appeared on plasma membrane and at acrosomal level. In conclusion, MF- ELF influence negatively spermatozoa first by impairing cell Ca 2+ homeostasis then by dramatically affecting sperm morphology and function. # 2006 Published by Elsevier Inc. Keywords: Boar; Spermatozoa; ELF; Animal model; Capacitation 1. Introduction In latest years, many efforts have been direct to study the effect of extremely low frequency magnetic field (MF-ELF) on human health. The state of alert to this problematic reflects the increasing use in modern society of the electricity and consequent impossibility to avoid exposure to MF produced by transmission and distribution of electric power (power lines) and by the myriad of devices used inside houses and work places. In parallel, epidemiological literature in the past 10 years have raised the possibility that may exist a direct correlation between MF exposure and chronic diseases. Even controversial, in fact, the exposition to MF has been correlated with an increased incidence of childhood malignancy, especially leukaemia, and there has also been considerable reports on possible occupational associations with cancer in adults, with cardiovascular www.theriojournal.com Theriogenology 67 (2007) 801–815 * Corresponding author. Tel. +39 0861411285; fax: +39 0861411285. E-mail address: bbarboni@uinte.it (B. Barboni). 0093-691X/$ – see front matter # 2006 Published by Elsevier Inc. doi:10.1016/j.theriogenology.2006.10.014