Gonadotropic activation induced by local photic stimulation of the lobus paraolfactorius in male quail.

Radioluminous material (RLM) was implanted in the paraolfactory area (a region which is linked to the gonadotropic infundibular complex by nervous pathways) of sexually quiescent quail exposed to short day lengths. Direct photic stimulation of the paraolfactory lobe (POL) resulted in significant testicular growth and increase in the plasma testosterone level. Red light (620 nm) emitting RLM was revealed to be somewhat more effective than green light (530 nm) emitting material. No difference appeared between the effect of local photostimulation of either the anterior or the posterior part of the POL. The gonadotropic response to paraolfactory lighting no longer occured after neural isolation of the infundibular complex.