PROLACTIN, GROWTH-HORMONE AND THE IMMUNE-SYSTEM IN HUMANS

Prolactin (PRL) and growth hormone (GPI) qualify as lymphoid growth an d differentiation factors. Yet, long-standing hyper- or hyposecretion of PRL or GH does not induce any significant alteration of the immune system. Subclinical changes in laboratory parameters (such as chemotax is or phagocytosis by granulocytes or macrophages or natural killer ce ll activity have been reported in some of these conditions. The GH-ins ulin-like growth factor (IGF)-I axis is dysregulated in ageing, in cat abolic states and in critical illness. Immune parameters, such as infe ction rate. are being monitored during clinical trials with GH or IGF- I, Hyperprolactinaemia may play an aggravating role in systemic lupus erythematosus, in autoimmune thyroiditis and in other autoimmune disea ses. The patient may benefit from increased alertness about interactio ns between the endocrine and immune systems.