Ob/ob mouse and Fa/Fa rat (what are they, who discovered them, when they were discovered, how was it discovered The Ob/ob mouse (i.e. obese mouse model) was first discovered in the Jackson laboratory in Bar Harbor, ME and is popular for studying Type 2 diabetes, food intake, and obesity. A recessive mutation on a certain chromosome in the mouse results in premature termination of leptin and therefore a deficiency of leptin in the mouse.

These ob/ob mice are hypherhagic and already obese at 2 weeks old. They also show other signs indicative of diabetes such as marked hyperglycemia, mildly impaired glucose tolerance, severe hyperinsulinemia, and impaired fertility and wound healing. They are also resistant to insulin. With all the signs of diabetes, the mice become severely and fatally diabetic with pancreatic collapse resulting in death.

The Zucker fa / fa (fatty) rat was discovered in 1961 and is a popular model for studying obesity and the prediabetic state. The state of the rat has come about due to an...

The rats are obese and hypherhagic with a large amount of subcutaneous fat at an early age. They also demonstrate hyperglycemia, insulin resistance, hyperlipidemia, and hyperinsulinemia. Their pancreatic cell numbers diminish as the rats grow.
Leptin (what is it, how it relates to the ob/ob mouse and fa/fa rat, who discovered it, how they discovered it, when it was discovered)

Leptin is a 16 kDa peptide which is predominantly produced by adipose tissue and plays an important role in regulating appetite and energy by its activity in the hypothalamus. Plasma leptin levels correspond to levels of adipose tissue and there is, therefore, a direct correspondence between levels of leptin and obesity / body fat.

Animals (such as rats or mice) deficit in leptin have greater amounts…