Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:4.6.1.2 (guanylate cyclase)
 8,497 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The soluble guanylate cyclase from rat lung was immobilized by absorption rather than covalent attachment on hexyl-, octyl-, or decyl-agarose. The enzyme retained activity after being bound to these matrices and could be compared to the soluble, mobile form of the enzyme. Compared to the soluble enzyme, the immobilized guanylate cyclase had a lower apparent maximal velocity and a higher apparent Km for MeGTP in the presence of Mg2+, Ca2+, or Mn2+. The apparent maximum velocity was reduced to the same extent by hexyl-, octyl-, or decyl-agarose, but the reduction in activity was greater with Mg2+ than with Ca2+ or Mn2+. Both the soluble and immobilized guanylate cyclase displayed concave downward patterns on double reciprocal polots as a function of Mn2+, and Ca2+ caused apparent activation of either form of the enzyme. MnATP appeared to be a linear competitive inhibitor with respect to MnGTP for both forms of the enzymes but the ki was 3 micron for the soluble form and 30 micron for the immobilized form. These results demonstrate that the soluble form of guanylate cyclase from rat lung retains many of its basic properties after being immobilized on a hydrophobic matrix; however, rather pronounced decreases in the maximum velocity and increases in the apparent Michaelis constant for MeGTP, particularly for MgGTP, are observed upon immobilization.
 ...
PMID:Immobilization of rat lung soluble guanylate cyclase on alkyl-agarose gels. 3 72

The effect of N-(omega-aminoalkyl) derivatives of naphthalene-1-sulfamide on the activity of soluble guanylate cyclase and on human platelet aggregation at the first (reversible) step of the guanylate cyclase reaction was studied. Low (approximately 10(-7)-10(-6) M) concentrations of the above compounds were shown to stimulate the guanylate cyclase activity; some derivatives caused simultaneous inhibition of platelet aggregation induced by ADP. Some fragments of the chemical structure of the molecules responsible for the enzyme activity regulation in the tested systems were identified. The naphthalene-1-sulfamide derivatives carrying 6-aminohexyl or 8-amino-octyl groups of the sulfamide substituent as well as chlorine atom at positions 4 or 5 of the naphthalene ring appeared to be the most potent activators of platelet guanylate cyclase and inhibitors of platelet aggregation at the reversible step of the enzymatic reaction.
 ...
PMID:[Effect of N-(6-aminohexyl)-5-chloronaphthalene-1-sulfamide (W-7) and its analogs on the activity of soluble guanylate cyclase and on human platelet aggregation]. 198 51

We conducted studies to investigate the nature and underlying mechanisms of the vascular effects of rutaecarpine (Rut), an alkaloid isolated from the Chinese herbal drug Evodia rutaecarpa. By using largely the effects on phenylephrine (PE)-induced contraction in the isolated rat aorta as the experimental index and by comparison with several known vascular muscle relaxants such as acetylcholine (ACh), histamine, and A23187, Rut relaxed PE-precontracted aorta in concentration-(10(-7)-10(-4) M) and endothelium-dependent manners. Studies with appropriate antagonists indicated that this was coupled to nitric oxide (NO) and guanylyl cyclase. Extracellular Ca2+ removal and treatment with the intracellular Ca2+ antagonist, 8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoate (TMB-8), suggested that influx of extracellular Ca2+ was the major factor contributing to the action of Rut. Pertussis toxin suppressed the relaxation potency of histamine but had no effects on the actions of Rut. NaF, the G proteins activator, attenuated the actions of ACh, but only minimally affected Na-NP, A23187, and Rut. 1-[6-{[17 beta-3-methoxyestra-1,2,3(10)-trien-17-yl]amino} hexyl]-1H-pyrrole-2,5-dione (U73122), the phospholipase C inhibitor, again suppressed the actions of ACh but had few effects on A23187 and Rut. Taken together, these results suggest that these vasorelaxants had different cellular mechanisms and that neither pertussis toxin-sensitive Gi protein, other G proteins, nor phospholipase C activation was involved in the cellular response to rutaecarpine.
 ...
PMID:Studies of the cellular mechanisms underlying the vasorelaxant effects of rutaecarpine, a bioactive component extracted from an herbal drug. 915 59

ATP/dithiothreitol (DTT)-stimulated guanylate cyclase (GC) in lung membrane was stimulated 18-fold by ATP and DTT, and both its activity and atrial natriuretic peptide (ANP)-stimulated GC activity were observed to be additive. ATP/DTT-stimulated GC was solubilized by octyl glucoside (OG) to examine the mechanism of ATP/DTT-stimulation. GC in OG-extracts was stimulated maximally 2.5-fold by both ATP, ATPgammaS or AMPPNP, and DTT. Preincubation of OG-extracts at 10 degrees C with AMPPNP and DTT (1st-preincubation) converted GC to an insensitive state to stimulation by both ATP and DTT, and this conversion was partly inhibited by a protein phosphatase-1 inhibitor (10-1,000 nM okadaic acid). On the other hand, ANP-stimulated GC was not converted to an insensitive state to ANP/ATP-stimulation by the 1st-preincubation. Subsequent preincubation of OG-extracts at 10 degrees C with both DTT and, ATP or ATPgammaS but not AMPPNP converted GC to a state sensitive to ATP/DTT-stimulation, and this conversion was partly inhibited by inhibitors of Ca2+/calmodulin-dependent protein kinase II (KN-62 and KN-93). In contrast, the preincubation with KN-62 and KN-93 had no effect on ANP-stimulated GC activity. The results suggested that phosphorylation was involved in the regulation of ATP/DTT-stimulated GC sensitivity to ATP/DTT-stimulation and that ATP/DTT-stimulated GC activity was likely to be a different type from ANP-stimulated GC activity.
 ...
PMID:Regulation of guanylate cyclase by ATP and dithiothreitol in rat lung membrane: involvement of an insensitive and a sensitive state to ATP/dithiothreitol-stimulation. 1208 46