Low doses of pulsed ultrasound and chromosomal abnormalities in male mouse germ cells

Abstract

Male mice were exposed to pulsed ultrasound (intensity less than 1 mW, frequency 3.5 MHz) for 30 min or to sham treatment. After 30 h, 11, 12 or 13 days, the testes were cytologically and histologically examined (using squash preparations, air-drying and sections). The resulting damage was studied at diakinesis-metaphase I and II, spermatogonial metaphase and anaphase. The investigation by air-drying did not show any significant increase in chromosome damage, 30 h, 11, 12 and 13 days after treatment (spermatogonial and spermatocytic metaphases). There was, however, a significant increase of the frequency of aneuploid cells detected at metaphase II. Investigations by squash techniques or sections did not reveal adverse effects on the spindles at spermatogonial and spermatocytic anaphases. We suggest that the reduction of fertility previously observed in our clinic could be explained by an increase of aneuploidy if germ cells are exposed to ultrasound during diakinesis of the first meiotic division.

Investigation into possible DNA damaging effects of ultrasound in occupationally exposed medical personnel — the alkaline comet assay study

“…The induction of single strand breaks was measured also by use of the single-cell gel electrophoresis (comet) assay on cultured Chinese hamster ovary (CHO) cells after exposure of cell suspensions to 2.17 MHz ultrasound Miller and Thomas, 1996). It was observed earlier that exposure to pulsed Doppler ultrasound induced sister chromatid exchanges (Barnett et al, 1987), and caused other detectable damage on the human genome (Garaj-Vrhovac and Kopjar, 1999a,b) as well as on male mouse germ cells (Moutschen et al, 1986). Ultrasound of diagnostic intensities impaired the DNA and growth patterns of animal cells (Fuciarelli et al, 1995;Liebeskind et al, 1979).…”

Effects of ultrasound on DNA and RNA synthesis in preimplantation mouse embryos

“…There have been very few animal studies, but in a study of chromosomal abnormalities in mouse male germ cells, low doses of pulsed ultrasound have been shown to result in a significant increase in aneuploid cells detected a t anaphase 11, suggesting errors in meiosis (Moutschen et al, 1986). It is important to know whether the chromosomal anomalies in the human oocytes could be a consequence of ultrasound exposure, and therefore, similar studies in mice are underway in our laboratory.…”

Etude cytogénétique de l'ovocyte humain

“…La preuve en est que, récemment, le contrôle ultrasonique de la croissance folliculaire a été mis en• cause en tant que générateur de non-disjonctions chromosomiques dans les ovo cytes [25]. The analysis of the distribution of non disjunction indicates that there is a significant diffe rence between observed non-disjunction and fre quencies expected from an equal partitioning of non-disjunction among ali chromosomes, especially in the D and G groups.…”