Nicotine-induced neuroepithelial cell changes in young rabbits: a preliminary communication

Nicotine, 1 mg/kg body weight/day, was injected subcutaneously in 3 female rabbits during gestational and lactating periods, and the lungs of the offspring were studied by scanning and transmission electron microscopy (SEM and TEM) on days 5, 10, and 25 postpartum. Three other female rabbits served as controls. The size and number of neuroepithelial bodies (NEB) as estimated by SEM were larger in the experimental group than in the control group, especially on days 5 and 25. Moreover, the NEB in the nicotine-exposed groups showed loss of normal boundaries and derangement of cells and granules by TEM. Neural components also became prominent. These findings suggest that chronic maternal exposure to nicotine may directly, or, through the neural route, indirectly induce hyperplasia and dysplasia of the NEB in the offspring of rabbits. Because NEB are suspected to regulate regional bronchial and vascular smooth muscle cells, such alterations may be similar to respiratory functional impairments found in infants of mothers who smoke.

Chronic bronchitis: a 10-year follow-up

A 10-year follow-up of 327 civil servants with bronchitis (301 men and 26 women) is presented. A further 14 were lost sight of during the period, so that the follow-up was 96% complete. More than one half (54%) of the men died during the 10-year period, some 57% of the deaths being attributed to respiratory causes and a further 8% to carcinoma of the bronchus. Mortality from these diseases was higher than among the general population, but other causes of death showed the normal pattern. The degree of dyspnoea noted at the first interview gave a useful estimate of prognosis, the mild, moderate, and severe groups showing progressively higher death rates. Neither the length of history nor the age at onset of symptoms could be related to mortality. The proportion of smokers among the patients was greater than expected in the general population, and although this may have been a factor contributing to the excess mortality of the group as a whole, it was not possible to determine any effect of smoking within this study.