Effect of Cell Density on Hormonal Secretion from Human Pituitary Adenomas in vitro

Abstract

Cell density effects were investigated on tumorous hormonal secretion from 10 pituitary adenomas: 3 somatotrophinomas secreting GH and PRL; 7 gonadotrophinomas, 3 co-secreted both FSH and LH, all 7 secreted LH. Enzymatically dispersed tissue was plated out in 24-well plates at 5 ×10⁵, 10⁵, 5 ×10⁴ and 10⁴ cells/well in serum-free media. Media were collected weekly for 2 weeks. Results: In 3 of 3 somatotrophinomas, GH and PRL secretion was higher (p < 0.05) at both week 1 and 2 from 10⁴ cells/well, but similar at other cell densities. In all 3 gonadotrophinomas, the FSH secretory rate was highest at 5 ×10⁵ cells/well which fell as cell density decreased. Conversely, in 7 of 7 gonadotrophinomas the LH secretory rate was highest at 10⁴ cells/well (p < 0.01) which fell as cell density increased. Conclusion: These data suggest that paracrine factors may modulate tumorous GH, PRL, FSH and LH secretion, and show that FSH and LH secretion vary inversely as cell density increases.

Hypogonadism in thalassemia major patients

“…The anterior pituitary gland is sensitive, in a dose-dependent fashion, to the effects of iron overload from transfusions [4] . Studies of human anterior pituitary adenomas showed that gonadotropes require more iron as compared with other pituitary cell types [5] . Thus, these cells are most affected, resulting in declining synthesis of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).…”

Effect of Iron Overload on Gonadotrophins and Organ Sex Steroids in Pubertal Thalassemia Patients

“…The prevalence and severity of hypogonadism in thalassemia major varies among studies, depending on the age group studied, genotype of thalassemia [17,18], extent of transfusion, age at the beginning and type of iron chelation therapy [18,19].The anterior pituitary gland is sensitive, in a dose-dependent fashion, to the effects of iron overload from transfusions [20]. Studies of human anterior pituitary adenomas showed that gonadotropes require more iron as compared with other pituitary cell types [21]. Thus, these cells are most affected, resulting in declining synthesis of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).…”

Hypogonadotropic Hypogonadism in a Female Patient with Thalassemia Major

“…NTBI is also a catalyst for the formation of reactive oxygen species, causing oxidative damage [1]. Studies of human anterior pituitary adenomas showed that gonadotropes require more iron as compared with other pituitary cell types [2]. Thus, these cells are most affected, resulting in declining synthesis of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).…”