Aging and the human pituitary gland.

Pituitary glands obtained at autopsy from 41 men (90 to 97 years old) and 45 women (90 to 98 years old) were studied histologically and immunohistochemically to determine the age-related alterations. Pituitaries from patients 30 to 39 years old (48 cases) and 60 to 89 years old (187 cases) were also studied and served as controls. Interstitial, perivascular fibrosis was seen in 88% of the aged adenohypophyses and, although significantly more intense than that in those of the fourth decade of life (P < 0.001), was similar to that noted in those of the seventh to ninth decades. Pituitaries of men were significantly more fibrotic than were those of women (P < 0.05). In proportion to the extent of fibrosis, the number of somatotrophs decreased in the lateral wings, whereas other cell types did not change quantitatively. Small deposits of amyloid and of iron were detected in seven and three cases, respectively. Squamous metaplasia in cells of the pars tuberalis was noted in 29%. The incidence of "basophil invasion" (the presence of corticotrophs in the posterior lobe) was 30%, a figure similar to that in younger controls. Granular cell tumorlets were detected in four aged neurohypophyses (5%), a frequency similar to that in control glands. Pituitary adenomas (two null cell, two lactotroph, and one corticotroph adenomas) were found of three men and two women in the study group. This 9% incidence of adenomas did not differ from that observed in the fourth decade (8%) or seventh decade (10%).(ABSTRACT TRUNCATED AT 250 WORDS)