Secretin and VIP-stimulated adenylate cyclase from rat heart. II. Impairment in spontaneous hypertension.
Cardiac adenylate cyclase activity was normal in 3 weeks-old spontaneously hypertensive rats of the Wistar-Okamoto substrain. The hormone-sensitive adenylate cyclase activity was reduced in 10 weeks-old or older animals, and secretin- and VIP-activations were definitely more impaired (by 64% and 69%, respectively) than isoproterenol- and glucagon-activations (17% and 22%, respectively). By contrast, the fluoride- and p[NH]ppG-stimulations of the enzyme were unaffected. These alterations in the adenylate cyclase system coupled to secretin and VIP appeared specific to the heart as the isolated pancreatic acinar cells from spontaneously hypertensive animals responded normally to secretin, as a liver particulate fraction responded normally to secretin and VIP, and both brain synaptic membranes and a particulate fraction of anterior pituitary to VIP.
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000375:Aging; D000818:Animals; D001921:Brain / Q000201:enzymology; D004789:Enzyme Activation; D005768:Gastrointestinal Hormones / Q000494:pharmacology*; D005934:Glucagon / Q000494:pharmacology; D006973:Hypertension / Q000201:enzymology*; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D008099:Liver / Q000201:enzymology; D008297:Male; D009206:Myocardium / Q000201:enzymology*; D010179:Pancreas / Q000201:enzymology; D010903:Pituitary Gland, Anterior / Q000201:enzymology; D051381:Rats; D012633:Secretin / Q000494:pharmacology*; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology*
D005768:Gastrointestinal Hormones; D012633:Secretin; D014660:Vasoactive Intestinal Peptide; D005934:Glucagon; D000262:Adenylyl Cyclases; D007545:Isoproterenol