Adenylate cyclase activity in microdissected rat liver tissue: periportal to pericentral activity gradient.
Adenylate cyclase activity was measured in microdissected samples from lyophilized cryostat sections of rat liver by means of an improved assay. Livers were obtained from adult Sprague-Dawley rats fasted for 22 hr. Adenylate cyclase activities, basal and those elicited by various agents, were determined in dissected samples from periportal and pericentral regions of the classic liver lobule. In all samples, enzyme activity was strongly stimulated by glucagon, cholera toxin, guanosine-5'-O-(3-thiotriphosphate), sodium fluoride and forskolin. The beta-adrenergic agonist isoproterenol produced very weak, if any, enzyme stimulation. Angiotensin II did not inhibit the activity elicited by lithium chloride and GTP at high concentrations, and pertussis toxin did not enhance the GTP-stimulated activity. We observed a periportal-to-pericentral gradient for basal and agent-stimulated activities.
German Cancer Research Center, Heidelberg.
C
C
Cortinovis
F
F
Klimek
E
E
Nogueira
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D002712:Chlorides / Q000494:pharmacology; D002772:Cholera Toxin / Q000494:pharmacology; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D005934:Glucagon / Q000494:pharmacology; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D006160:Guanosine Triphosphate / Q000494:pharmacology; D007545:Isoproterenol / Q000494:pharmacology; D008094:Lithium / Q000494:pharmacology; D018021:Lithium Chloride; D008099:Liver / Q000187:drug effects / Q000201:enzymology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012969:Sodium Fluoride / Q000494:pharmacology
D002712:Chlorides; D000804:Angiotensin II; D005576:Colforsin; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D006160:Guanosine Triphosphate; D012969:Sodium Fluoride; D005934:Glucagon; D002772:Cholera Toxin; D008094:Lithium; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; D018021:Lithium Chloride; D007545:Isoproterenol