Central dopamine D2 receptors regulate growth-hormone-dependent body growth and pheromone signaling to conspecific males.

NOAÍN, D; PÉREZ-MILLÁN, MI; BELLO, EP; LUQUE, GM; CASAS CORDERO, R; GELMAN, DM; PEPER, M; GARCÍA-TORNADÚ, I; LOW, MJ; BECÚ-VILLALOBOS, D; RUBINSTEIN, M

JOURNAL OF NEUROSCIENCE

SOC NEUROSCIENCE

Lugar: Washington; Año: 2013 vol. 33 p. 5834 - 5842

0270-6474

Competition between adult males for limited resources such as food and receptive females is shaped by the male pattern of pituitarygrowth hormone (GH) secretion that determines body size and the production of urinary pheromones involved in male-to-male aggression.Inthe brain, dopamine (DA) provides incentive salienceto stimulithat predictthe availability offood and sexual partners. Althoughthe importance of the GH axis and central DA neurotransmission in social dominance and fitness is clearly appreciated, the two systemshave always been studied unconnectedly. Here we conducted a cell-specific genetic dissection study in conditional mutant mice thatselectively lack DA D2 receptors (D2R) from pituitary lactotropes (lacDrd2KO) or neurons (neuroDrd2KO). Whereas lacDrd2KO micedeveloped a normal GH axis, neuroDrd2KO mice displayed fewer somatotropes; reduced hypothalamic Ghrh expression, pituitary GHcontent, and serum IGF-I levels; and exhibited reduced body size and weight. As a consequence of a GH axis deficit, neuroDrd2KO adultmales excreted low levels of major urinary proteins and their urine failed to promote aggression and territorial behavior in control malechallengers, in contrast to the urine taken from control adult males. These findings reveal that central D2Rs mediate a neuroendocrineexocrinecascade that controls the maturation of the GH axis and downstream signals that are critical for fitness, social dominance, andcompetition between adult males.