Effects of Acetazolamide on the Development of Mouse Limb Buds In Vitro

Forelimb buds of mouse embryos were cultured in a serum‐free BGJb medium by a roller system. At the beginning of culture, acetazolamide was added to the final concentration of 10 −5 M or 10 −4 M. After 6 days of culture, no morphological abnormalities of the developing forelimb buds could be detected. In morphometrical analyses, the morphological scores of antebrachium and hand in the right forelimb of female embryos were 1.8 and 2.2 in the 10 −5 M and 10 −4 M acetazolamide‐treated groups, respectively, and 1.6 in controls. There was no difference in the size of the forelimb among these groups. Concerning cartilage skeleton, the incidence of bending of the ulnoradius was increased to 64–90% in 10 −4 M acetazolamide‐treated group, which was different from the control (0.22%). In addition, there was a significant difference in the protein and DNA contents in only right forelimb buds between the acetazolamide‐treated and control groups. However, there were no differences in sex or laterality in the development of forelimbs and cartilage skeleton. No pathological changes in the cartilage skeleton and mesenchyme were observed in the acetazolamide‐treated forelimbs. From these findings, there is the possibility that acetazolamide per se may primarily interfere with the development of the forelimb in mouse embryos at the molecular level in vitro.