OCCURRENCE OF DEOXYRIBONUCLEIC-ACID FRAGMENTATION DURING PROLACTIN-INDUCED STRUCTURAL LUTEOLYSIS IN CYCLING RATS

Citation
S. Matsuyama et al., OCCURRENCE OF DEOXYRIBONUCLEIC-ACID FRAGMENTATION DURING PROLACTIN-INDUCED STRUCTURAL LUTEOLYSIS IN CYCLING RATS, Biology of reproduction, 54(6), 1996, pp. 1245-1251
Citations number
46
Categorie Soggetti
Reproductive Biology
Journal title
ISSN journal
00063363
Volume
54
Issue
6
Year of publication
1996
Pages
1245 - 1251
Database
ISI
SICI code
0006-3363(1996)54:6<1245:OODFDP>2.0.ZU;2-J
Abstract
We determined whether fragmentation of genomic DNA, one of the hallmar ks of apoptosis, occurs during structural luteolysis in cycling rats. Corpora lutea (CL) were collected from rats at each estrous cycle stag e (1800 h), and fragmented DNA was extracted. Only CL from rats at the proestrous stage showed distinct DNA fragmentation. To determine the period of occurrence of DNA fragmentation, CL were collected at severa l points between 1200 h on the day of proestrus and 0600 h on the day of estrus. Distinct DNA fragmentation was observed from 1800 h (proest rus) to 2400 h (proestrus), and the extent was significantly lower at 0600 h (estrus). It is known that prolactin (PRL) induces structural l uteolysis in rats. To examine the role of PRL in luteal DNA fragmentat ion, 2-bromo-alpha-ergocryptine (BE) was used to suppress the PRL surg e on the day of proestrus. CL collected at 1800 h from BE-treated rats did not show distinct DNA fragmentation, and PRL injection offset the effect of BE. Histochemical analysis with a 3'-end labeling technique confirmed the occurrence of DNA fragmentation in luteal tissue. These results suggest that apoptotic cell death occurs during PRL-induced s tructural luteolysis.