18 Vivarium, 18 Synchronous

Cosmos 1129 Russian Hardware Suite

The basis for the present study was to determine if the lesions that were seen in the olfactory, but not respiratory, nasal mucosa of rodents in the experiment flown onboard Apollo-17 would be repeated. A further rationale involved the fact that the olfactory sense in rodents influences mating behavior. Thus, should these lesions develop during flight, with presumably impaired olfactory sense, they might be a contributing cause of the failure to mate seen in the rat ontogenesis experiment, should that indeed have been the case.

After decalcification, each specimen (consisting of the remainder of the head after removal of brain, pituitary, eyes and mandible) was divided coronally into three segments, so that respiratory mucosa, predominating in the anterior, and olfactory mucosa, more abundant in the posterior portion, could be studied without having to make numerous serial or step sections. In evaluating the tissues micro- scopically, slides were read without knowing the identity of the tissues until all had been examined. Any lesions found were scored on the basis of their severity and extent.

Lesions similar to those in the Apollo-17 flight animals were not found, leaving their etiology still in doubt. The posterior regions of the olfactory nasal mucosa of flight rats failed to reveal any histopathological changes. However, in the anter- ior aspect of the nasal cavity of the flight rats, focal lesions of moderate severity and variable extent were seen. These were consistent in character with that of a mild virus infection, which, it is postulated, was self-limiting. The infection was present in all groups of animals: flight, synchronous, and vivarium control. This is not to say that the animals are not to be considered specific pathogen free (SPF), for it is only reasonable to expect SPF animals to become infected from random sources after they leave the SPF environment. In any case, the results seem to illustrate the effect that stress, as exemplified by actual or simulated space flight, may have on an enzootic infection, even though it may have been subclin- ical in character.

Kraft, L.M.: Studies of the Nasal Mucosa. Final Reports of U.S. Rat Experiments Flown on the Soviet Satellite Cosmos 1129. M.R. Heinrich and K.A. Souza, eds., NASA TM-81289, 1981, pp. 405-414.

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