Linked Life Data

9356220

Source:http://linkedlifedata.com/resource/pubmed/id/9356220

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1998-2-4
pubmed:abstractText
The presence of multiple forms of gonadotropin-releasing hormone (GnRH) within a single brain is common among vertebrate species. In previous studies of reptiles, two forms of GnRH were isolated from the brain of alligators and the primary structure was determined to be that of chicken (c)GnRH-I and cGnRH-II. GnRH has also been detected by indirect methods in other reptiles including turtles, lizards, and snakes. We used a combination of high-performance liquid chromatography (HPLC) and radioimmunoassay to determine the number and molecular form(s) of GnRH in the brain of a lizard, Anolis carolinensis, that was reported to lack GnRH cells in the forebrain. Immunoreactivity was detected in the same HPLC elution position in which synthetic cGnRH-II elutes, but not in any other position. Detection was based on five antisera that among them detect the 12 known forms of GnRH; these antisera include ones that are specific to cGnRH-I and cGnRH-II. We conclude that the lizard A. carolinensis contains cGnRH-II, but not cGnRH-I or another known form of GnRH. These data, coupled with our earlier immunocytochemical study, suggest that the lizard studied here lacks cGnRH-I, the form that is found in the terminal nerve, olfactory bulb, and forebrain in nonsquamate reptiles and in birds. Our hypothesis is that the presence of both cGnRH-I and cGnRH-II in the brain is ancestral in the reptilian lineage and retained in the orders that include turtles (Chelonia) or alligators (Crocodilia). However, the pattern in the order Squamata varies: in A. carolinensis, only cGnRH-II is present in the brain and cGnRH-I is absent, whereas in the snake Thamnophilis sirtalis, cGnRH-I is retained and cGnRH-II is absent in the brain, as recently reported. This raises the question of how reproduction is controlled in reptiles that lack one form of GnRH.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0016-6480
pubmed:author
pubmed:copyrightInfo
Copyright 1997 Academic Press. Copyright 1997 Academic Press
pubmed:issnType
Print
pubmed:volume
108
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
247-57
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Immunoreactive gonadotropin-releasing hormone (GnRH) is detected only in the form of chicken GnRH-II within the brain of the green anole, Anolis carolinensis.
pubmed:affiliation
Department of Biology, University of Victoria, Victoria, British Columbia, V8W 2Y2, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't