PMID- 11246211
OWN - NLM
STAT- MEDLINE
DCOM- 20010531
LR  - 20190906
IS  - 0021-9967 (Print)
IS  - 0021-9967 (Linking)
VI  - 432
IP  - 3
DP  - 2001 Apr 9
TI  - Influence of sex and estrus cycle on the sexual dimorphisms of the hypothalamic 
      ventromedial nucleus: stereological evaluation and Golgi study.
PG  - 329-45
AB  - Neurons in the ventromedial nucleus of the hypothalamus (VMN) display structural 
      and biochemical sex differences in response to estrogen. Despite this fact, 
      reports on sex differences in the morphology of the VMN are restricted to its 
      volume and synaptic patterning. The aim of this study was to characterize the 
      neuroanatomical sexual dimorphisms in the VMN and to investigate whether 
      endogenous changes in ovarian steroid secretion influence such dimorphisms. The 
      VMN of adult male rats and intact, aged-matched female rats killed on proestrus 
      and diestrus day 1 was examined by using stereological methods applied to 
      conventionally stained sections and Golgi-impregnated material. The VMN contained 
      55,000 neurons in rats of both sexes, but its volume was, on average, 1.25 times 
      larger in males than in females. The volume was greater in proestrus than in 
      diestrus rats due to parallel changes in the neuronal somatic size. Unlike the 
      dorsomedial division, neurons in the ventrolateral division had longer dendritic 
      trees in proestrus than in diestrus females and males. The spine density was 
      consistently higher in females than in males in both VMN divisions. In addition, 
      in the ventrolateral part the magnitude of the sex differences varied across the 
      estrus cycle, and reached the greatest value when females were in proestrus. The 
      volume of the neuropil was significantly larger in males than in females, and was 
      not affected by the estrus phase. Our results reveal that the magnitude of the 
      neuroanatomical sex differences in the VMN vary across the estrus cycle due to 
      the trophic influence of estrogen upon its neurons. They also show that the 
      fundamental sex difference in the structure of the VMN is accounted for by the 
      neuropil components.
CI  - Copyright 2001 Wiley-Liss, Inc.
FAU - Madeira, M D
AU  - Madeira MD
AD  - Department of Anatomy, Porto Medical School, Alameda Prof. Hernani Monteiro, 
      4200-319 Porto, Portugal. madeira@med.up.pt
FAU - Ferreira-Silva, L
AU  - Ferreira-Silva L
FAU - Paula-Barbosa, M M
AU  - Paula-Barbosa MM
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Comp Neurol
JT  - The Journal of comparative neurology
JID - 0406041
SB  - IM
MH  - Animals
MH  - Cell Nucleus/ultrastructure
MH  - Dendrites/ultrastructure
MH  - Estrus/*physiology
MH  - Female
MH  - Golgi Apparatus/ultrastructure
MH  - Male
MH  - Neurons/cytology
MH  - Neuropil/cytology
MH  - Rats/*anatomy & histology/*physiology
MH  - Rats, Wistar
MH  - *Sex Characteristics
MH  - Ventromedial Hypothalamic Nucleus/*anatomy & histology/cytology/*physiology
EDAT- 2001/03/14 10:00
MHDA- 2001/06/02 10:01
CRDT- 2001/03/14 10:00
PHST- 2001/03/14 10:00 [pubmed]
PHST- 2001/06/02 10:01 [medline]
PHST- 2001/03/14 10:00 [entrez]
AID - 10.1002/cne.1106 [doi]
PST - ppublish
SO  - J Comp Neurol. 2001 Apr 9;432(3):329-45. doi: 10.1002/cne.1106.