Serotonin, Norepinephrine, and the Hypothalamic Ventromedial Nucleus: a Proposed Mechanism Mediating Hyperphagia and Obesity Page: 40

                                
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anterior to EBZ) and did not extend posteriorly past 3.43 mm
anterior to EBZ.  They were generally localized in a small
area encompassing the VMH nucleus. A large lesion track of
destroyed tissue was seen in only one brain. One rat did
not show a lesion or a lesion track. Lesions generally
included the hypothalamic ventromedialis nucleus, the
arcuatus nucleus, portions of the hypothalamic dorsomedialis
nucleus, pars ventralis, and sometimes the periventricularis
nucleus. Lesions averaged an anterior-posterior distance of
approximately 1500 microns.
The second run lesions generally were much larger and
damaged a much greater proportion of the diencephalon.
Lesions were often visible in section 4.23 mm anterior to
EBZ though not in the VMH nucleus. Usually if the lesion
appeared so far anteriorly, it was dorsal to the VMH. Often
it would be seen in or above the hypothalamic dorsomedialis,
pars dorsalis. Usually around 4.23 mm anterior to EBZ, the
lesion would begin to encroach upon the VMH nucleus.
Generally, it would obliterate all of the posterior portion
of the nucleus and often extended back as far as 3.18 mm
anterior to EBZ or even 2.97 mm anterior to EBZ (not shown)
which includes the nucleus mammallaris medialis, pars
lateralis. The lesion generally included the hypothalamic
dorsomedialis nucleus, pars ventralis and pars dorsalis, the
ventromedialis nucleus, the arcuatus nucleus, the