PMID- 7889117
OWN - NLM
STAT- MEDLINE
DCOM- 19950418
LR  - 20190904
IS  - 0918-8959 (Print)
IS  - 0918-8959 (Linking)
VI  - 41
IP  - 5
DP  - 1994 Oct
TI  - Microinjection of LHRH and its antagonistic analog into the medial preoptic area 
      does not affect pulsatile secretion of LH in ovariectomized rats.
PG  - 559-63
AB  - To gain a better understanding of the existence of an ultra-short feedback 
      mechanism controlling LHRH secretion in the medial preoptic area (MPO), we 
      examined the effects of microinjections of LHRH or the LHRH antagonist [D-pGlu1, 
      D-Phe2, D-Try3,6] into the MPO on pulsatile secretion of LH in ovariectomized 
      rats and on the surge of LH secretion in proestrous rats. Neither the injection 
      of 10 ng LHRH nor 100 ng its antagonist into the MPO had any effect on pulse 
      frequency or the mean LH concentration in ovariectomized rats. The injection of 
      100 ng LHRH antagonist or 10 ng LHRH delayed or advanced, respectively, the LH 
      surge in proestrous rats. Taking these results together with our previous report, 
      the present study indicates that 1) endogenous LHRH in the MPO is involved in the 
      ultra-short feedback regulation of LHRH release and 2) the ultra-short positive 
      feedback mechanism in the MPO acts at the time of the proestrous LH surge but not 
      under a hormonal milieu as in ovariectomized rats.
FAU - Funabashi, T
AU  - Funabashi T
AD  - Department of Physiology, Yokohama City University School of Medicine, Japan.
FAU - Hashimoto, R
AU  - Hashimoto R
FAU - Jinnai, K
AU  - Jinnai K
FAU - Kimura, F
AU  - Kimura F
LA  - eng
PT  - Journal Article
PL  - Japan
TA  - Endocr J
JT  - Endocrine journal
JID - 9313485
RN  - 33515-09-2 (Gonadotropin-Releasing Hormone)
RN  - 68059-94-9 (LHRH, pGlu(1)-Phe(2)-Trp(3,6)-)
RN  - 9002-67-9 (Luteinizing Hormone)
RN  - SZB83O1W42 (Pyrrolidonecarboxylic Acid)
SB  - IM
MH  - Animals
MH  - Feedback
MH  - Female
MH  - Gonadotropin-Releasing Hormone/administration & dosage/*analogs & 
      derivatives/antagonists & inhibitors/*pharmacology
MH  - Luteinizing Hormone/*metabolism
MH  - Microinjections
MH  - Ovariectomy
MH  - Preoptic Area/*physiology
MH  - Pulsatile Flow
MH  - Pyrrolidonecarboxylic Acid/analogs & derivatives
MH  - Rats
MH  - Rats, Wistar
EDAT- 1994/10/01 00:00
MHDA- 1994/10/01 00:01
CRDT- 1994/10/01 00:00
PHST- 1994/10/01 00:00 [pubmed]
PHST- 1994/10/01 00:01 [medline]
PHST- 1994/10/01 00:00 [entrez]
AID - 10.1507/endocrj.41.559 [doi]
PST - ppublish
SO  - Endocr J. 1994 Oct;41(5):559-63. doi: 10.1507/endocrj.41.559.