GnRH production/release is one of the few confirmed examples of behavior influencing hormones, rather than the other way around. [ citation needed ] Cichlid fish that become socially dominant in turn experience an upregulation of GnRH secretion whereas cichlid fish that are socially subordinate have a down regulation of GnRH secretion.  Besides secretion, the social environment as well as their behavior affects the size of GnRH neurons . Specifically, males that are more territorial have larger GnRH neurons than males that are less territorial. Differences are also seen in females, with breeding females having smaller GnRH neurons than control females.  These examples suggest that GnRH is a socially regulated hormone.
Because steroids are lipophilic, they diffuse easily through the cell membranes, and therefore have a very large distribution volume. In their target tissues, steroids are concentrated by an uptake mechanism which relies on their binding to intracellular proteins (or " receptors ", see below). High concentration of steroids are also found in adipose tissue, although this is not a target for hormone action. In the human male, adipose tissue contains aromatase activity, and seems to be the main source of androgen-derived estrogens found in the circulation. But most of the peripheral metabolism occurs in the liver and to some extent in the kidneys, which are the major sites of hormone inactivation and elimination, or catabolism (see below).