Fluorometric detection of implantation sites in rats

A new fluorescent technique is proposed for detecting implantation sites in the rat, based on the binding capacity of tetracycline. Both intraluminal (20 μg/kg) and intravenous (8.3 mg/kg) administrations of tetracycline permit the macroscopic visualization (under 366 nm of ultraviolet light) of implantation sites, since they show a lower flurescence (LFS) than the remaining endometrium (FS). Greater binding a tritiated tetracycline was observed in nonimplantation sites (176 to 56 × 103 dpm/mg protein) than in implantation sites (P < 0.05).