Figure 3.

Quantitative aspects of the ORX-IR and the MCH-IR innervation of GnRH neurons in the INF of human male subjects. The percentages of GnRH-IR perikarya receiving ORX-IR and MCH-IR contacts (A), the mean incidences of ORX-IR and MCH-IR afferent contacts on the perikarya of GnRH neurons (B), the average number of axo-dendritic contacts per 1 mm GnRH dendrite (C) and the relative incidences of axo-dendritic vs. axo-somatic juxtapositions (D) were determined from five adult male human individuals. Note that GnRH neurons in these studies receive about twice as many inputs from ORX-IR neurons than from MCH-IR ones and both types of input preferentially target the dendritic compartment of GnRH neurons.