Adrenergic stimulation of inositol-phosphate production in a genital tract smooth muscle cell line.
Catecholamines are important in the modulation of smooth muscle contractile activity; this study was undertaken to evaluate adrenoceptor stimulation of intracellular inositol-phosphate production in a genital tract smooth muscle myocyte. DDT1 MF-2 smooth muscle myocytes, derived from a hamster ductus deferens leiomyosarcoma, were loaded with 3H-inositol, incubated in 10 mM LiCl, then stimulated with adrenergic agonists with and without antagonists. Subsequently, the inositol phosphates were isolated by anion-exchange chromatography. In the presence of norepinephrine (NE), inositol trisphosphate (IP3) was produced by 30 s and peaked at 2 min; inositol 1-phosphate was also apparent by 30 s, and continued to increase over 15 min. Clonidine (an alpha-2 agonist), isoproterenol, and NE in the presence of phentolamine or prazosin (an alpha-1 antagonist) failed to increase IP3. In contrast, NE in the presence of yohimbine (an alpha-2 antagonist) or propranolol stimulated IP3 production to levels comparable to that stimulated by NE alone. These studies provide evidence that inositol phosphate production is involved in alpha-1 adrenergic signal transduction in DDT1 MF-2 myocyte.
Phillippe
M
M
Department of Obstetrics and Gynecology, Michael Reese Hospital and Medical Center, University of Chicago, Illinois.
Bangalore
S
S
D000322:Adrenergic Agonists / Q000494:pharmacology*; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000818:Animals; D002395:Catecholamines / Q000494:pharmacology; D002460:Cell Line; D006224:Cricetinae; D004305:Dose-Response Relationship, Drug; D005834:Genital Neoplasms, Male / Q000378:metabolism / Q000473:pathology; D007295:Inositol Phosphates / Q000378:metabolism*; D007890:Leiomyosarcoma / Q000378:metabolism / Q000473:pathology; D008297:Male; D008647:Mesocricetus; D009130:Muscle, Smooth / Q000378:metabolism / Q000473:pathology*; D009638:Norepinephrine / Q000494:pharmacology; D010646:Phentolamine / Q000494:pharmacology; D011224:Prazosin / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D014407:Tumor Cells, Cultured / Q000378:metabolism / Q000473:pathology; D015016:Yohimbine / Q000494:pharmacology
D000322:Adrenergic Agonists; D000317:Adrenergic alpha-Antagonists; D002395:Catecholamines; D007295:Inositol Phosphates; D015016:Yohimbine; D011433:Propranolol; D009638:Norepinephrine; D011224:Prazosin; D010646:Phentolamine