Adrenergic stimulation of diacylglycerol production in genital tract smooth muscle myocytes.
Diacylglycerol (DAG) production has not been reported in previous studies that have characterized inositol phosphate production during alpha-1 adrenergic receptor signal transduction in the DDT1 MF-2 genital tract myocytes. The current study sought to measure norepinephrine (NE)-stimulated DAG production in these transformed myocytes utilizing thin layer chromatography. DAG production was characterized as an alpha-1 adrenergic mediated event utilizing subtype specific adrenergic agonist and antagonists. DAG production occurred in response to physiologic concentration of NE, was apparent by 30 s and was significantly increased by 2 min. Maximal DAG production was unaffected by pretreatment of the myocytes for 96 h with testosterone, which has previously been shown to induce a doubling of alpha-1 adrenergic receptors in these cells. In contrast, testosterone pretreatment did result in a shift of the dose-response curve resulting in a significantly lower EC50 for NE in the treated cells compared to control myocytes. In conclusion, these studies have confirmed that DAG production occurs as a component of alpha-1 adrenergic signal transduction in the DDT1 MF-2 myocytes; transduction events that were modulated by testosterone resulting in increased agonist sensitivity.
Austin
R J
RJ
University of Chicago, Pritzker School of Medicine, Department of Obstetrics and Gynecology, Chicago, Illinois 60637.
DiGiovonni
L
L
Phillippe
M
M
D000818:Animals; D002460:Cell Line; D006224:Cricetinae; D004075:Diglycerides / Q000096:biosynthesis*; D005837:Genitalia, Male / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008647:Mesocricetus; D009130:Muscle, Smooth / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011941:Receptors, Adrenergic / Q000187:drug effects / Q000502:physiology*; D013565:Sympatholytics / Q000494:pharmacology; D013566:Sympathomimetics / Q000494:pharmacology; D013739:Testosterone / Q000494:pharmacology
D004075:Diglycerides; D011941:Receptors, Adrenergic; D013565:Sympatholytics; D013566:Sympathomimetics; D013739:Testosterone