Background Preclinical experimental studies revealed an acute alteration of pituitary adenylate cyclase-activating polypeptide in response to a single activation of the trigeminovascular system, which suggests a potential role of pituitary adenylate cyclase-activating polypeptide in the pathogenesis of migraine. However, changes in pituitary adenylate cyclase-activating polypeptide after repeat...

The effect of cholera toxin on activation of adenylate cyclase by the endogenous Ca2+-binding protein, calmodulin, GTP, dopamine, and forskolin was investigated in bovine striatum. Adenylate cyclase activity was measured in washed membrane fractions prepared from homogenates that had been preincubated with cholera toxin. Pretreatment of striatal membranes with cholera toxin increased the respon...

This study examined the effect of metal ions Ca2+, Mg2+, and Mn2+ and sonication on ejaculated frozen-thawed bovine sperm adenylate cyclase activity, and whether cAMP levels in sperm changed during capacitation with heparin. The sperm adenylate cyclase was almost insensitive to Ca2+ at concentrations up to 10 mM when cold-shocked homogenized spermatozoa were used. Adenylate cyclase activity, as...

Nitroimidazole is an antibiotic and radiosensitizer chemical with great potentials in imaging. The hepato-cytoxicity evaluation of nitroimidazole and possible energy status changes in liver cells due to its anti-inflammatory characteristics are crucial in tumor imaging and chemotherapy. Adenylate cyclase is key enzyme to cause energy imbalance leading to cytotoxicity. To evaluate energy status ...

Chronic treatment of rats with haloperidol causes behavioral supersensitivity to dopaminergic agonists and an increase in the sensitivity of adenylate cyclase activity in the striatum to stimulation by dopamine. In this study the authors examined whether chronic treatment with haloperidol could elicit a change in sensitivity of adenylate cyclase in the striatum of the rat for guanyl nucleotides...

A plasma membrane fraction was prepared from pig kidney medulla. It contained lysine-vasopressin-sensitive adenylate cyclase activity (maximum activation: 4to 6fold, apparent Km value for the hormone: about 5 X 1OV M). Lysine-vasopressin was not inactivated by the membrane preparation even at low hormonal concentrations. The specific [3H]lysine-vasopressin (vasopressin) binding sites found are ...

Antipsychotic drugs and their clinically impotent congeners were examined as inhibitors of dopamine-sensitive adenylate cyclase (EC 4.6.1.1) in cell-free membrane preparations of the caudate-putamen of rat brain. Of 12 neuroleptic drugs with reported antipsychotic efficacy, all inhibit stimulation of adenylate cyclase by 40 muM dopamine at micromolar concentrations. Among 14 other structurally ...

The ejaculated porcine spermatozoa were fractionated into the cytosol, membrane, midpiece plus tail (flagella) and head fractions, and their adenylate cyclase activities were measured. About 65% of the total activity was located in the flagella fraction. For all the fractions, Mn2+-dependent adenylate cyclase activity was about 20 times higher than Mg2+-dependent activity, and guanine nucleotid...

To identify the GTP-binding site of catecholamine-stimulated adenylate cyclase (EC 4.6.1.1) from pigeon erythrocyte membranes photoreactive GTP derivatives have been synthesized. One of them, P”-(4-azidoanilido)-PI-5’-guanosine triphosphate, proved to be a potent activator of particulate and soluble adenylate cyclase which binds with high affinity (K,,ss 3.3 x lo-’ M) and competes effectively w...

The interaction of forskolin with adenylate cyclase was studied by evaluating its effect on metal and metalATP kinetics and by measuring its protective effect when the enzyme was subjected to denaturation conditions. The solubilized calmodulinand forskolin-sensitive adenylate cyclase from brain and the particulate enzyme from platelets were inactivated upon preincubation with N-ethylmaleimide. ...