Harderian glands

In an animal study of rats exposed by inhalation to ethylene oxide at 10, 33, or 100 ppm for approximately two years (245), and in a separate chronic rat study in which rats were exposed to 50 or 100 ppm of ethylene oxide (240), increased incidences of mononuclear cell leukemia, peritoneal mesothelioma, and various brain tumors have been reported. In an NTP (246) two-year inhalation study of mice at 50 and 100 ppm, alveolar/bronchiolar carcinomas and adenomas, papillary cystadenomas of the harderian gland, and malignant lymphomas, uterine adenocarcinomas, and mammary gland tumors were increased in one or both exposure groups. 

Harderian gland porphyrins in, 4, 382 Harderoporphyrin, 4, 382 Harmala alkaloids, 4, 529 Harmaline... 

Buzzell G.R. (1996). The Harderian gland — perspectives. Micro Res Tech 34, 2-5. 

Rehorek S., Hillenius W., Quan W., Halpem M., et al. (2000). Passage of Harderian gland secretions to the vomeronasal organ of Thamnophis sirtalis (Colubridae). Can J Zool 78, 1284-1288. 

Thiessen, D. D. andHarriman, A. E. (1986) Harderian gland exudates in the male Meriones unguic-ulatus regulate female proceptive behavior, aggression, and investigation. J. Comp. Psychol. 100, 85-87. 

Pancreatic islet-cell neoplasia in rats Harderian-gland neoplasia in mice... 

The Harderian gland, wrapped behind the eyeball, is especially prominent in rodents. It produces a variable, primarily lipid secretion and drains through the Harderian-lacrymal tract and the external nares. In Mongolian gerbils, the secretion is spread over the body during grooming (Thiessen ct ah, 1976). A pheromonal function has not been clearly established. 

As expected, castration affects gland size, activity, and composition of the secretion profoundly. Eor example, castration changes the levels of porphyrins, indoles, and proteins in the Harderian gland secretion of the Syrian hamster (Buzzelletflk, 1991). 

Thiessen, D. D., Clancy, A., and Goodwin, M. (1976). Harderian gland pheromone in the Mongolian gerbil Meriones unguiculatus. Journal of Chemical Ecology 2,231-238. 

Two-year inhalation studies (6 hours/day, 5 days/week for 103 weeks) in rodents showed clear evidence of carcinogenicity. Mice exposed at 375 and 750ppm had increased incidences of harderian gland adenomas and carcinomas female mice exposed at 188 and 750 ppm had increased liver neoplasms female rats in the 188 and 375ppm-exposed groups had increased incidences of mammary gland fibroadenomas and carcinomas. Other treatment-related effects were an increase in nasal lesions and degeneration of the respiratory epithelium in mice. 

Rostral extremity of left orbit Intra-orbital (Harderian) gland... 

Nitromethane was tested for carcinogenicity by inhalation in one experiment in mice and in two experiments in rats. In mice, it increased the incidence of Harderian gland and lung tumours in males and females as well as of hepatocellular adenomas in females. In one experiment in rats, nitromethane increased the incidence of benign and malignant mammary gland tumours in females, but produced no increase in the incidence of tumours in a second study in a different strain of rat. 

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