Age and gender-related differences in mitral cells of olfactory bulb.

OBJECTIVE To investigate the age and gender-related differences in mitral cells of the human cadaveric olfactory bulbs. STUDY DESIGN A cross-sectional study. PLACE AND DURATION OF STUDY The study was conducted in the Department of Anatomy, University of Health Sciences, Lahore, from August 2005 to July 2007. METHODOLOGY Sixty olfactory bulbs, 30 each from male and female (age 20-76 years) human cadavers divided into six groups of age and gender-wise were collected from the mortuary of the King Edward Medical University, Lahore. Mitral cells were counted and their diameter was calculated from 10 microm thick cresyl violet stained histological sections. Statistical analysis was done using ANOVA for age-related differences and independent t-test for gender-related differences. RESULTS There was significant reduction in the number of mitral cells and diameter of their nuclei with age. There was significant decrease in the number of mitral cells in males, between groups I and II (p < 0.001); II and III (p < 0.001); and I and III (p < 0.001); statistically significant decrease also occurred in females, between groups IV and V (p < 0.001); V and VI (p < 0.001); and IV and VI (p < 0.001). In most cases, the distance between individual mitral cells was seen to be much greater than in younger group. In group VI, few mitral cells were observed in the cell layer. There was also significant decrease in the diameter of mitral cell nuclei in males, between groups I and III (p < 0.001); and II and III (p < 0.010); in females, between groups IV and VI (p < 0.001); and V and VI (p < 0.001). No gender-related differences were observed. CONCLUSION The number of mitral cells and diameter of their nuclei decreased with advancing age.