Changes in plasma hormone profiles after tumor transplantation into syngeneic and allogeneic rats

Abstract

Transplantation of 2 chemically (DMBA, MCA)-induced tumors into syngeneic female or male DA strain rats elicited hormonal changes during tumor growth. Plasma levels of 7 different hormones were studied. Tumor cells in syngeneic recipients produced a biphasic decrease in insulin, an early increase in prolactin, and a late-phase decrease in thyroxine. Corticosterone decreased in female tumor bearers but increased in males. This difference may reflect differences in the tumors transplanted. Male rats had a decrease in testosterone during the late phase of tumor growth, while females had a biphasic decrease in progesterone and a late-phase increase in growth hormone. The tumors used were moderately immunogenic in syngeneic recipients. However, tumor transplantation to allogeneic recipients produced an early decrease in growth hormone and no change in insulin, corticosterone or thyroxine. Further, transplantation of normal liver cells to syngeneic or allogeneic recipients produced no hormonal abnormalities. This study demonstrates that hormonal changes which are not observed with normal cells or allogeneic tumor transplantation can occur within 2 days of syngeneic tumor transplantation. Progressive tumor growth is characterized by a worsening endocrine imbalance which involves multiple hormone systems.

Catecholamine, Indoleamine and Corticosteroid Responses in Mice Bearing Tumors

“…These endocrine imbalances occur very early and late after tumor transplantation [47]. Early changes occurred 16-48 h after tumor transplantation, while late-phase defects developed during the last few days of life [47]. In contrast to the study of Normann et al [48], we observe only a small increase in plasma concentrations of corticosterone.…”

“…It is known that endocrine balance is affected by tumor cell administration [47,48]. These endocrine imbalances occur very early and late after tumor transplantation [47].…”

“…These endocrine imbalances occur very early and late after tumor transplantation [47]. Early changes occurred 16-48 h after tumor transplantation, while late-phase defects developed during the last few days of life [47].…”

Pituitary-Thyroid Axis and Immune System: A Reciprocal Neuroendocrine-lmmune Interaction

“…At the thyroid level, it has been demonstrated that thymectomized mice show morphological alterations of thyroidal cells with reduced thyroid hormone production, which can be reversed by a thymus graft [57], Quite a similar histological picture of the thyroid has been observed in athymic nude mice [58], ' With regard to peripheral immune functions, the first suggestions were offered by those studies reporting plas ma thyroid hormone changes after activation of the im mune system [1,59], The immune responses to innocuous antigens such as SRBC or trinitrophenyl hemocyanin are associated with reduced levels of thyroid hormones in blood [59]. A progressive decrease of T4 blood levels is also observed after inoculation of cells from methylcholanthrene or dimethylbenzanthracene-induced tumors [60] . The lack of correlation between the progression of the tumor and the observed endocrine alteration suggests that the changes in thyroid hormone blood levels are not directly mediated by tumor cell products but rather con stitute a host response to endogenously induced media tors capable of affecting neuroendocrine mechanisms.…”

Interactions Between Immune System Parameters and Thyroid Status in People From Radioactive Contaminated Areas by the Conditions of Emotional Stress

“…Синдром еутиреоїдної слабкості може проявлятися у випадках, коли продукція ТТГ змінилася незначною мірою. Дані експери-ментів стали підставою для припущення, що причиною зниження вмісту тиреоїдних гормонів наразі є імуносупресія, зумовлена стресом чи радіаційним впливом і зниженням кількості імунних клітин-продуцентів ТТГ [18]. Розглядається можливість включення у процес екстрагіпофізарного ТТГ, синтезова-ного імунокомпетентними клітинами, котрі мігрували до щитоподібної залози [19].…”