Registration Dossier

Toxicological information

Additional toxicological data

Currently viewing:

Administrative data

Endpoint:
additional toxicological information
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
supporting study
Study period:
no data available
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Well-documented paper on the activation of ovulated mouse oocytes by Sr-supplemented culture medium.

Data source

Reference
Reference Type:
publication
Title:
Developmental potential and chromosome constitution of strontium-induced mouse parthenogenones
Author:
O'Neill G.T.; et al.
Year:
1991
Bibliographic source:
Molecular reproduction and Development 30, 214-219

Materials and methods

Type of study / information:
Experimental data on reproductive toxicity
Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
In vitro activation of mouse oocytes
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
- Name of test material (as cited in study report): Strontium chlroide
No further details are given.

Results and discussion

Any other information on results incl. tables

Brief exposure of recently ovulated mouse oocytes in M16 embryo culture medium supplemented with 1.6 mM SrCl2 for 2-10 min resulted in induction of a high incidence of parthenogenones. A lower incidence of activation and a significant rate of oocyte degeneration were observed when oocytes were incubated in M16 Sr2+ medium for 20-60 min. The majority of oocytes exposed to M16 Sr2+ for 2-10 min developed as single-pronuclear haploid parthenogenones (1PN). The incidence of this parthenogenetic class was reduced as the exposure time to M16 Sr2+ was increased from 2 to 30 min. Under these conditions a greater proportion of the activated oocytes developed as two-pronuclear diploid parthenogenones, due to the failure of second polar body extrusion. The activation frequency and the proportionate incidence of the pathways of parthenogenetic development following the exposure of ovulated oocytes to Ca-free M16 medium differed significantly from that induced by M16 Sr2+. Cytogenetic analysis of the single-pronuclear haploid class of Sr2+ induced parthenogenones at metaphase of the first-cleavage mitosis showed that this agent did not induce an increased incidence of chromosome segregation errors during the completion of the second meiotic division. Analysis of the developmental potential of the two-pronuclear class of diploid Sr2+ induced parthenogenones during the pre-implantation stages of embryogenesis revealed that their cell number and rate of cell division were less than those of fertilised embryos retained either in vivo or in vitro.

Applicant's summary and conclusion

Conclusions:
see "remarks on results"