Induction of Pseudopregnancy in Rat by Silver Nitrate on Nasal Mucosa

Abstract

Physiologic relationship of nasal and genital regions has been described chiefly by Fliess 1 and Brettauer. 2 Recent studies have been made by Collip and his collaborators. 3 Suggestive clinical observations by one of us (Rosen) stimulated a series of laboratory experiments in an effort to establish evidence of a specific nasogenital mechanism. Results reported herein are taken from a large and varied group of experiments.

Adult female albino rats, from an inbred colony, were used. They were isolated from males, fed a diet of hospital table scraps supplemented with greens, Pablum, powdered milk, and cod liver oil. The regularity and the nature of the sexual cycles of all the stock females were determined from vaginal smears. Only rats with regular 4 or 5 day cycles were used. After the observation of 4 to 6 consecutive regular cycles, treatment consisting in the application of silver nitrate solution to the mucosa of the conchae was started. The silver nitrate solution was applied in one group with a fine cotton applicator; in a second group, by instillation of 0.05 cc. AgNo₃ using a tuberculin syringe. The time of treatment was: (a) during the proestrus and estrus of 2 consecutive cycles, a total of 6 days with interruption by 2 rest days, and (b) during diestrus, proestrus, estrus and diestrus, a total of 6 days application. This second type of treatment was more generally used. Certain animals received 10%, others 20% and still others 50% (gm., %) solutions during entire treatment period; others received progressively increased doses of 10, 20, 50% for 2 days each. Two control studies were made by (a) using NaCl (0.9%) and (b) applying silver solutions to the buccal mucosa. All cases, experimental and control, were treated under light ether anesthesia.