ABSTRACT
The contraceptive properties of a gel formulation containing sodium lauryl sulfate were investigated in both in vitro and in vivo models. Results showed that sodium lauryl sulfate inhibited, in a concentration-dependent manner, the activity of sheep testicular hyaluronidase. Sodium lauryl sulfate also completely inhibited human sperm motility as evaluated by the 30-sec Sander-Cramer test. The acid-buffering capacity of gel formulations containing sodium lauryl sulfate increased with the molarity of the citrate buffers used for their preparations. Furthermore, experiments in which semen was mixed with undiluted gel formulations in different proportions confirmed their physiologically relevant buffering capacity. Intravaginal application of the gel formulation containing sodium lauryl sulfate to rabbits before their artificial insemination with freshly ejaculated semen completely prevented egg fertilization. The gel formulation containing sodium lauryl sulfate was fully compatible with nonlubricated latex condoms. Taken together, these results suggest that the gel formulation containing sodium lauryl sulfate could represent a potential candidate for use as a topical vaginal spermicidal formulation to provide fertility control in women.
Subject(s)
Sodium Dodecyl Sulfate/pharmacokinetics , Spermatocidal Agents , Animals , Buffers , Chemistry, Pharmaceutical , Condoms , Gels , Humans , Hyaluronoglucosaminidase/metabolism , Hydrogen-Ion Concentration , In Vitro Techniques , Male , Nonoxynol/pharmacology , Rabbits , Sheep , Sodium Dodecyl Sulfate/administration & dosage , Sodium Dodecyl Sulfate/chemistry , Sperm Motility/drug effects , Spermatozoa/drug effects , Spermatozoa/enzymologyABSTRACT
OBJECTIVE: The objective of the present study was to look at the effect of a protein-rich diet on cyclosporine A (CsA)-induced acute nephrotoxicity in rodents using markers of tubular damage. DESIGN: Female Sprague-Dawley rats were conditioned to either a standard or a casein-rich diet for 2 weeks. Then, they were given CsA intraperitoneally (25 mg/kg/24 h or an equivalent volume of vehicle (Cremophor EL; Sigma Chemical Co, St. Louis, MO) for 7 days at 7 AM. RESULTS: During CsA treatment, bodyweight, caloric consumption, water intake, and urine output were not significantly different in animals fed with the standard Rat Chow and those on the high-protein feeding. On days 1 and 7, the 24-hour urine excretion of N-acetyl-beta-d-glucosaminidase (NAG) and beta-galactosidase (beta-GAL) were significantly (P < .001) lower in CsA-treated rats on the high-protein diet than in those on the standard Rat Chow. After 7 days of treatment with CsA, no significant difference in the renal function level was found between rats fed with the standard or the casein-rich diet. The post-necrotic cellular regeneration in renal cortex was significantly lower (p<0.001) in CsA-treated rats on the high-protein than on the standard diet. In CsA-treated rats on the standard diet, immunogold labeling showed a massive and specific concentration of the drug into lysosomes of proximal tubular cells. Contrastingly, no gold particle was found over the lysosomes of animals given the rich-protein feeding. CONCLUSION: In our current experimental conditions, a protective effect of high-casein diet against CsA-induced proximal tubular damage was observed in Sprague-Dawley rats.
