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Updated: Aug 23, 2026

Remote Neuronal Activation Coupled with Automated Blood Sampling to Induce and Measure Circulating Luteinizing Hormone in Mice
Published on: August 25, 2023
Luteinizing hormone and prolactin are not retrograde transferred in perihypophyseal vascular complex in ewes
Janina Skipor1, Waldemar Grzegorzewski, Barbara Wasowska
1Institute of Animal Reproduction and Food Research of the Polish Academy of Sciences, Tuwima 10, 10-747 Olsztyn, Poland. jskip@pan.olsztyn.pl
Abstract:
The objective of the study was to determine whether luteinizing hormone (LH) and prolactin (PRL) can access the brain by way of transfer from the venous blood of the cavernous sinus to the arterial blood supplying the brain and hypophysis. Studies were performed on heads of 22 mature sheep isolated during different phases of the estrous cycle and perfused with autologous blood. We were not able to demonstrate any transfer of LH and PRL in the investigated periods. This suggests that molecular weight of hormone may be a main factor determining the permeation and transfer of hormones in the perihypophyseal vascular complex.
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