The effect of salivary gland extirpation upon rabbit uroparotin excretion.

Animals and materials Healthy male rabbits of about 2. 5kg body weight were kept in individual cages under a carefully controlled condition and their whole urines were collected daily to extract crude uroparotin according to the procedure previously described(Ito and Yamamoto, 1958). The extirpation of the salivary gland After the normal urine of each rabbit was collected as an intact control for not less than 5 weeks, the extirpation of the salivary gland was carried out in 3 groups as follows, (A)both parotid and submaxillary gland, (B)parotid gland, and(C) submaxillary gland. The urine collection and extraction of crude uroparotin were carried out immediately or at the 4th week following the operation, and the combined crude uroparotin obtained during a week were compared with the initial urine, concerning the yield and activity. At the end of the experiments, some rabbits of each group were killed and examined to see whether the salivary gland had been removed completely and also if the regeneration had occurred. Bioassay The biological activities were estimated using the hypocalcemic activity and leucocytosis producing activity, and expressed by the term of a minimum effective dose per kg body weight. Unlike human uroparotin in which the biological activity showed a seasonal variation. (Ito and Yamamoto, 1959b), no such variation has been demonstrated in rabbits**. It is therefore unnecessary to take the seasonal influences into consideration in the present study. Administration of parotin Some rabbits of group A were injected intravenously with 100mg of parotin daily for 12 days(total amount of 1, 200mg)from the 41st week after the operation, and the alteration on the excretion of uroparotin activity into urine was examined.