Severity: Warning
Message: file_get_contents(https://...@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests
Filename: helpers/my_audit_helper.php
Line Number: 143
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 143
Function: file_get_contents
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 209
Function: simplexml_load_file_from_url
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3098
Function: getPubMedXML
File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 316
Function: require_once
Severity: Warning
Message: Attempt to read property "Count" on bool
Filename: helpers/my_audit_helper.php
Line Number: 3100
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3100
Function: _error_handler
File: /var/www/html/application/controllers/Detail.php
Line: 574
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 488
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 316
Function: require_once
Ovarian follicles of Xenopus laevis frogs consist of a single large oocyte surrounded by follicle cells attached to the oocyte by gap junctions. Adenosine has been found to activate an outward K+ current in follicles. This response is reduced by microinjection of protein kinase inhibitor (PKI), suggesting that adenosine 3',5'-cyclic monophosphate (cAMP) mediates the response. To investigate this further, we verified previous studies that indicate that several methods of elevating cAMP in follicles activate hyperpolarizing outward currents. The potency of two adenosine analogues to hyperpolarize follicles, 5'-N-ethylcarboxamidoadenosine (NECA) greater than cyclopentyladenosine, is indicative of A2 receptors that are characteristically coupled to adenylyl cyclase. We also report for the first time that another stimulator of adenylyl cyclase, follicle-stimulating hormone (FSH), also induces a hyperpolarizing current in follicles which is carried by K+ and attenuated by injection of PKI. We used a novel procedure to completely remove follicle cells from oocytes. Intact follicles, but not oocytes completely stripped of follicle cells, hyperpolarized in response to FSH, NECA, dibutyryl cAMP, microinjected cAMP, and forskolin, but not to dideoxyforskolin (which does not activate adenylyl cyclase). Injection of the catalytic subunit of cAMP-dependent protein kinase (which is too large to traverse gap junctions) into oocytes of intact follicles failed to activate a K+ current. These data suggest that FSH and adenosine hyperpolarize follicles by stimulating adenylyl cyclase and that cAMP-dependent protein kinase must be activated on both sides of follicle cell-oocyte gap junctions to elicit a hyperpolarizing K+ current.
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Source |
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http://dx.doi.org/10.1152/ajpcell.1990.259.5.C775 | DOI Listing |
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