Matches in SemOpenAlex for { <https://semopenalex.org/work/W2001779420> ?p ?o ?g. }
- W2001779420 endingPage "1911" @default.
- W2001779420 startingPage "1905" @default.
- W2001779420 abstract "The suppression during lactation of pulsatile LH release and pituitary GnRH receptors has been attributed to a primary deficit in hypothalamic GnRH release. In the present investigation we have attempted to characterize the responsiveness of the lactational hypothalamus using the excitatory amino acid receptor agonist N-methyl-aspartic acid (NMA) to stimulate LH and PRL secretion. Lactating rats were ovariectomized on day 2 postpartum, and their litters were adjusted to eight pups. Dual venous catheters were implanted 6-7 days later, and rats were fitted with protective tethers and jackets for chronic pulsatile infusions of GnRH and NMA. GnRH pulses (5 or 10 ng/pulse once every 50 min) were administered for 20 h to upregulate GnRH receptors and restore pituitary responsiveness to GnRH. Rats were then infused with NMA (40 mg/kg BWpulse) once every 50 min for four pulses or once every 2 h over a 24-h period. Blood samples were collected at 10-min intervals at times surrounding the final two GnRH pulses, the first several NMA pulses, and the final three NMA pulses 24 h later. Samples were analyzed for LH and PRL by RIA. Procedural control experiments were performed in normal adult rats with NMA administered at 20 mg/kg BW-pulse in males and at 20 and 40 mg/kg BW-pulse in females. Whereas normal rats responded to NMA pulses with unambiguous LH and PRL peaks, lactating rats failed to show LH responses either acutely or after 24 h of treatment. PRL responses to the drug depended upon the circulating levels of the hormone immediately preceding each NMA pulse. When levels were elevated (presumably due to intermittent suckling by the pups), NMA infusion resulted in an acute suppression of PRL. When PRL levels were low, NMA appeared to neither stimulate nor inhibit this hormone. These data suggest that GnRH release from the hypothalamus of the lactating rat is refractory to NMA stimulation, perhaps due to suckling-induced activation of endogenous opioid peptide or γ-aminobutyric acid systems that could suppress GnRH neurons. Conversion of the PRL response from stimulation by NMA in normal animals to inhibition during lactation might be attributed to simultaneous activation of both dopamine neurons and the PRL-releasing factor system. According to this hypothesis, the response to NMA would be dominated by PRL releasing factor in normal rats and by dopamine in lactating animals, which have a lower dopamine turnover rate and thus a greater potential for becoming activated by NMA. (Endocrinology124: 1905-1911,1989)" @default.
- W2001779420 created "2016-06-24" @default.
- W2001779420 creator A5026104880 @default.
- W2001779420 creator A5029682703 @default.
- W2001779420 creator A5073019775 @default.
- W2001779420 date "1989-04-01" @default.
- W2001779420 modified "2023-10-11" @default.
- W2001779420 title "Qualitative Changes in Luteinizing Hormone and Prolactin Responses to<i>N</i>-Methyl-Aspartic Acid during Lactation in the Rat*" @default.
- W2001779420 cites W1993789735 @default.
- W2001779420 cites W2001081446 @default.
- W2001779420 cites W2001599410 @default.
- W2001779420 cites W2008547960 @default.
- W2001779420 cites W2012557066 @default.
- W2001779420 cites W2012597943 @default.
- W2001779420 cites W2017407623 @default.
- W2001779420 cites W2021944586 @default.
- W2001779420 cites W2039382429 @default.
- W2001779420 cites W2040675458 @default.
- W2001779420 cites W2043066409 @default.
- W2001779420 cites W2043535801 @default.
- W2001779420 cites W2049942626 @default.
- W2001779420 cites W2054924571 @default.
- W2001779420 cites W2058662134 @default.
- W2001779420 cites W2063524589 @default.
- W2001779420 cites W2069519891 @default.
- W2001779420 cites W2069927404 @default.
- W2001779420 cites W2071272820 @default.
- W2001779420 cites W2071693558 @default.
- W2001779420 cites W2081928466 @default.
- W2001779420 cites W2085446091 @default.
- W2001779420 cites W2085972388 @default.
- W2001779420 cites W2124403509 @default.
- W2001779420 cites W2128188572 @default.
- W2001779420 cites W2148234133 @default.
- W2001779420 cites W2180941170 @default.
- W2001779420 cites W2027294327 @default.
- W2001779420 doi "https://doi.org/10.1210/endo-124-4-1905" @default.
- W2001779420 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/2647467" @default.
- W2001779420 hasPublicationYear "1989" @default.
- W2001779420 type Work @default.
- W2001779420 sameAs 2001779420 @default.
- W2001779420 citedByCount "65" @default.
- W2001779420 countsByYear W20017794202012 @default.
- W2001779420 countsByYear W20017794202013 @default.
- W2001779420 countsByYear W20017794202016 @default.
- W2001779420 countsByYear W20017794202023 @default.
- W2001779420 crossrefType "journal-article" @default.
- W2001779420 hasAuthorship W2001779420A5026104880 @default.
- W2001779420 hasAuthorship W2001779420A5029682703 @default.
- W2001779420 hasAuthorship W2001779420A5073019775 @default.
- W2001779420 hasConcept C126322002 @default.
- W2001779420 hasConcept C134018914 @default.
- W2001779420 hasConcept C170493617 @default.
- W2001779420 hasConcept C185592680 @default.
- W2001779420 hasConcept C2776659692 @default.
- W2001779420 hasConcept C2777003273 @default.
- W2001779420 hasConcept C2777658017 @default.
- W2001779420 hasConcept C2778575703 @default.
- W2001779420 hasConcept C2778782382 @default.
- W2001779420 hasConcept C2778894405 @default.
- W2001779420 hasConcept C2778938600 @default.
- W2001779420 hasConcept C2779064019 @default.
- W2001779420 hasConcept C2779234561 @default.
- W2001779420 hasConcept C54355233 @default.
- W2001779420 hasConcept C71315377 @default.
- W2001779420 hasConcept C71924100 @default.
- W2001779420 hasConcept C79191276 @default.
- W2001779420 hasConcept C8264082 @default.
- W2001779420 hasConcept C86803240 @default.
- W2001779420 hasConceptScore W2001779420C126322002 @default.
- W2001779420 hasConceptScore W2001779420C134018914 @default.
- W2001779420 hasConceptScore W2001779420C170493617 @default.
- W2001779420 hasConceptScore W2001779420C185592680 @default.
- W2001779420 hasConceptScore W2001779420C2776659692 @default.
- W2001779420 hasConceptScore W2001779420C2777003273 @default.
- W2001779420 hasConceptScore W2001779420C2777658017 @default.
- W2001779420 hasConceptScore W2001779420C2778575703 @default.
- W2001779420 hasConceptScore W2001779420C2778782382 @default.
- W2001779420 hasConceptScore W2001779420C2778894405 @default.
- W2001779420 hasConceptScore W2001779420C2778938600 @default.
- W2001779420 hasConceptScore W2001779420C2779064019 @default.
- W2001779420 hasConceptScore W2001779420C2779234561 @default.
- W2001779420 hasConceptScore W2001779420C54355233 @default.
- W2001779420 hasConceptScore W2001779420C71315377 @default.
- W2001779420 hasConceptScore W2001779420C71924100 @default.
- W2001779420 hasConceptScore W2001779420C79191276 @default.
- W2001779420 hasConceptScore W2001779420C8264082 @default.
- W2001779420 hasConceptScore W2001779420C86803240 @default.
- W2001779420 hasIssue "4" @default.
- W2001779420 hasLocation W20017794201 @default.
- W2001779420 hasLocation W20017794202 @default.
- W2001779420 hasOpenAccess W2001779420 @default.
- W2001779420 hasPrimaryLocation W20017794201 @default.
- W2001779420 hasRelatedWork W140074805 @default.
- W2001779420 hasRelatedWork W2020625803 @default.
- W2001779420 hasRelatedWork W2024126057 @default.
- W2001779420 hasRelatedWork W2040330521 @default.
- W2001779420 hasRelatedWork W2052716760 @default.