Blood and tissue concentrations of many other hormones remain unchanged (TSH, thyroid hormones, ADH, PTH, prolactin, and glucocorticoids). Despite unchanging hormone levels, some endocrine tissues become less responsive to stimulation. For example, there is less GH (growth hormone) and insulin secreted after a carbohydrate-rich meal or during a glucose tolerance test.
Peripheral tissues become less responsive to some hormones, particularly glucocorticoids and ADH. The failure to produce enough glucocorticoids can affect metabolism and the inability to deal with stress. In addition, a decline in production will also reduce the anti-inflammatory and immunosuppressive qualities that they give. This means that the elderly are more prone to pain and infections.