Inferred network

R(Retina) → MPN(Medial preoptic nucleus)
MPN(Medial preoptic nucleus) → VTA(Ventral tegmental area)
VTA(Ventral tegmental area) → LPO(Lateral preoptic area)
LPO(Lateral preoptic area) → LHA(Lateral hypothalamic area)

Support information about direct projections from Retina to Medial preoptic nucleus:
Sending structure Receiving structureStrength of projection Type of connectionTechniqueGeneral descriptionCollatorAssociated reference
RetinaMedial preoptic nucleus light/moderatenot knownCholera toxin conjugated to HRP
Case pg348,349, fig5a-f. Soma notes 36 female Sprague-Dawley rats weighing 200-350g. 10 microliters of CT-HRP(.20%-.40%) were injected into one eye ?behind the lens into the vitreous chamber of the eye. pressure injection over 1 min. Terminal notes Medial component of the RHT included labeled fibres and terminals found near the midline involved the medial half of the medial preoptic area terminals evident in the ventral part of the medial preoptic nucleus.
Levine JD, Weiss ML, Rosenwasser AM, Miselis RR., 1991

Support information about direct projections from Medial preoptic nucleus to Ventral tegmental area:
Sending structure Receiving structureStrength of projection Type of connectionTechniqueGeneral descriptionCollatorAssociated reference
Medial preoptic nucleusVentral tegmental area lightnot knownHRP/WGA
Case table1. Soma notes WGA-HRP inj. Terminal notes not specified..
Chiba T, Murata Y., 1985

Support information about direct projections from Ventral tegmental area to Lateral preoptic area:
Sending structure Receiving structureStrength of projection Type of connectionTechniqueGeneral descriptionCollatorAssociated reference
Ventral tegmental areaLateral preoptic area moderatenot knownfluorescent tracers
Case pg369-71. Soma notes many neurons (several 100/12u section). Terminal notes FB inj.
Faye-Lund H., 1985

Support information about direct projections from Lateral preoptic area to Lateral hypothalamic area:
Sending structure Receiving structureStrength of projection Type of connectionTechniqueGeneral descriptionCollatorAssociated reference
Lateral preoptic areaLateral hypothalamic area lightnot knownHRP/WGA
Case pg427, fig5. Soma notes not specified.. Terminal notes WGA-HRP inj into depressor sites, core of inj site in LHAp/LHAt/VTA/SN.
Allen GV, Cechetto DF., 1993
Lateral preoptic areaLateral hypothalamic area existsnot knownautoradiography
earlier: Nauta Brain 81:319, 1958; cat, Nauta method
Swanson L.W., 1976