Figure 2.

Loss of either Arrb1^−/− or Arrb2^−/− does not affect buserelin-triggered LH secretion. Serum LH levels were measured by RIA. Mice were either left untreated or treated with saline or 3 ng buserelin/g body weight. Twenty minutes later, blood was collected and serum prepared. Buserelin-triggered LH levels in Arrb1^−/− (A) and Arrb2^−/− (B) mice were significantly higher (P < .001) than levels from their respective untreated and saline-treated controls. Buserelin-triggered LH levels were not different (P > .2) between Arrb1^−/− (A) and Arrb2^−/− (B) mice and their WT littermate controls, respectively. Only male mice were used to preclude the effects of estrous cycle variation on GnRH secretion in females. Error bars represent SEM.