Adipocyte studies: systems for investigating effects of growth hormone and other chronically acting hormones

Adipose tissue is very amenable to study in vitro. Collagenase digestion yields free adipocytes which usually respond well to acute stimulation/inhibition by hormones and other factors. Chronic effects of hormones are best studied using explants of adipose tissue which, from some species (e.g. sheep), can be maintained in culture for up to a week without loss of function. Alternatively, pre-adipocytes can be readily isolated from adipose tissue and induced to proliferate and differentiate in culture, while various adipocyte-like cell-lines have been established, which can be used for chronic studies. Use of these various systems for investigating the mechanisms of action of growth hormone are described.