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| Publications [#163496] of Leonard E. White
search PubMed.Papers Published
- WJ George, LJ Ignarro, LE White (1975). Muscarinic stimulation of cardiac guanylate cyclase.. Recent advances in studies on cardiac structure and metabolism, UNITED STATES, 7, 381-90.
(last updated on 2009/09/16)
Abstract: Right ventricular kitten papillary muscles were incubated with dibutyryl adenosine 3',5'-monophosphate (db-cAMP) at varying concentrations from 1 X 10(-4) M to 1 X 10(-3) M. A positive inotropic effect was observed with all concentrations of db-cAMP. Concomitant administration of 5 X 10(-4) M monobutyryl guanosine 3',5'-monophosphate and 1--2 X 10(-4) M db-cAMP did not produce an inotropic response. At the biochemical level cardiac guanyl cyclase activity is enhanced 2--3 times with acetylcholine and this enhancement is completely blocked by atropine. This increased activity appears to be the result of a decrease in the Michaelis constant (Km) for GTP. Calcium also produces a significant activation of guanyl cyclase activity.
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