PMID- 20002963
OWN - NLM
STAT- MEDLINE
DCOM- 20100818
LR  - 20220318
IS  - 1365-2826 (Electronic)
IS  - 0953-8194 (Linking)
VI  - 22
IP  - 2
DP  - 2010 Feb
TI  - Effects of photoperiod on kisspeptin neuronal populations of the ewe diencephalon 
      in connection with reproductive function.
PG  - 110-8
LID - 10.1111/j.1365-2826.2009.01939.x [doi]
AB  - Kisspeptin (Kiss) is a key regulator of reproductive function in both prepubertal 
      and adult mammals. Its expression appears to vary throughout the year in seasonal 
      species. We aimed to determine the impact of a change of photoperiod on the size 
      of Kiss neuronal populations found in the preoptic area (POA) and arcuate nucleus 
      (ARC) of the ewe brain. Using immunocytochemistry, we first examined the 
      proportion of neurones expressing Kiss, using HuC/D as a neuronal marker, at 
      different time-points after transition from long days (LD; 16 : 8 h light/dark 
      cycle) to short days (SD; 8 : 16 h light/dark cycle). Luteinising hormone (LH) 
      secretion was measured in ovariectomised oestradiol replaced ewes from the month 
      preceding the transition to SD until the sacrifice of the animals at days 0, 45 
      and 112 from this photoperiodic transition. High LH levels were only observed in 
      animals killed at day 112. The number of Kiss neurones/mm(2) doubled in the 
      caudal ARC at day 112. The percentage of neurones showing Kiss immunoreactivity 
      increased significantly in both the POA and ARC in the day 112 group. In a second 
      experiment, ewes kept in LD received an i.c.v. injection of colchicine 20 h 
      before sacrifice. Colchicine treatment increased the number and the percentage of 
      neurones with Kiss in both the POA and caudal ARC. The data obtained suggest that 
      the increase in Kiss neurones detected in the POA and caudal ARC after transition 
      to SD stemmed from an increase in Kiss synthesis. This up-regulation of Kiss 
      content under the shorter day condition appears to be a late event within the 
      cascade activated by a longer secretion of melatonin, which is a critical factor 
      in switching gonadotrophin-releasing hormone secretion to a breeding season 
      profile.
FAU - Chalivoix, S
AU  - Chalivoix S
AD  - INRA, UMR85 Physiologie de la Reproduction et des Comportements, Nouzilly, 
      France.
FAU - Bagnolini, A
AU  - Bagnolini A
FAU - Caraty, A
AU  - Caraty A
FAU - Cognie, J
AU  - Cognie J
FAU - Malpaux, B
AU  - Malpaux B
FAU - Dufourny, L
AU  - Dufourny L
LA  - eng
PT  - Journal Article
DEP - 20091204
PL  - United States
TA  - J Neuroendocrinol
JT  - Journal of neuroendocrinology
JID - 8913461
RN  - 0 (Central Nervous System Agents)
RN  - 4TI98Z838E (Estradiol)
RN  - 9002-67-9 (Luteinizing Hormone)
RN  - SML2Y3J35T (Colchicine)
SB  - IM
MH  - Animals
MH  - Arcuate Nucleus of Hypothalamus/drug effects/*metabolism
MH  - Cell Count
MH  - Central Nervous System Agents/pharmacology
MH  - Circadian Rhythm/drug effects/physiology
MH  - Colchicine/pharmacology
MH  - Darkness
MH  - Diencephalon/drug effects/metabolism
MH  - Estradiol/metabolism
MH  - Female
MH  - Immunohistochemistry
MH  - Luteinizing Hormone/blood/metabolism
MH  - Neurons/drug effects/*metabolism
MH  - Ovariectomy
MH  - *Photoperiod
MH  - Preoptic Area/drug effects/*metabolism
MH  - Sheep
MH  - Time Factors
EDAT- 2009/12/17 06:00
MHDA- 2010/08/19 06:00
CRDT- 2009/12/17 06:00
PHST- 2009/12/17 06:00 [entrez]
PHST- 2009/12/17 06:00 [pubmed]
PHST- 2010/08/19 06:00 [medline]
AID - JNE1939 [pii]
AID - 10.1111/j.1365-2826.2009.01939.x [doi]
PST - ppublish
SO  - J Neuroendocrinol. 2010 Feb;22(2):110-8. doi: 10.1111/j.1365-2826.2009.01939.x. 
      Epub 2009 Dec 4.