Biomaterial Database

Adenosine interaction with adenylate cyclase in rat posterior pituitary. 1988

M B Anand-Srivastava

Clinical Research Institute of Montreal, Que., Canada.

An adenosine-sensitive adenylate cyclase has been demonstrated in rat posterior pituitary in the present studies. N-Ethylcarboxamide adenosine (NECA), 2-chloroadenosine (2-Cl-Ado) and L-N6-phenylisopropyladenosine (PIA) all stimulated adenylate cyclase in a concentration-dependent manner, with an apparent Ka between 0.5 and 1 microM. NECA was most effective and stimulated adenylate cyclase by about 100%, whereas 2-Cl-Ado and PIA stimulated the enzyme activity by about 60%. The activation of adenylate cyclase by NECA was dependent on the concentrations of metal ions such as Mg2+ or Mn2+. The stimulatory effect of NECA on adenylate cyclase was completely blocked by 3-isobutyl-1-methylxanthine (IBMX) and 8-phenyltheophylline. Adenosine showed a biphasic effect on adenylate cyclase: stimulation at lower concentrations and inhibition at higher concentrations, whereas 2'-deoxyadenosine and 2'5'-dideoxyadenosine inhibited adenylate cyclase in a concentration-dependent manner. In addition, dopamine, isoproterenol and forskolin also stimulated adenylate cyclase to various degrees and the stimulatory effect of isoproterenol and forskolin was found to be additive with the stimulation exerted by NECA. These data indicate the presence of adenosine stimulatory receptors Ra/A2 in posterior pituitary which are coupled to adenylate cyclase. It is possible that adenosine may act as one of the important regulators to regulate and/or modulate the release of posterior pituitary hormones.

UI	MeSH Term	Description	Entries
D010904	Pituitary Gland, Posterior	Neural tissue of the pituitary gland, also known as the neurohypophysis. It consists of the distal AXONS of neurons that produce VASOPRESSIN and OXYTOCIN in the SUPRAOPTIC NUCLEUS and the PARAVENTRICULAR NUCLEUS. These axons travel down through the MEDIAN EMINENCE, the hypothalamic infundibulum of the PITUITARY STALK, to the posterior lobe of the pituitary gland.	Neurohypophysis,Infundibular Process,Lobus Nervosus,Neural Lobe,Pars Nervosa of Pituitary,Posterior Lobe of Pituitary,Gland, Posterior Pituitary,Infundibular Processes,Lobe, Neural,Lobes, Neural,Nervosus, Lobus,Neural Lobes,Pituitary Pars Nervosa,Pituitary Posterior Lobe,Posterior Pituitary Gland,Posterior Pituitary Glands,Process, Infundibular,Processes, Infundibular
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D011983	Receptors, Purinergic	Cell surface proteins that bind PURINES with high affinity and trigger intracellular changes which influence the behavior of cells. The best characterized classes of purinergic receptors in mammals are the P1 receptors, which prefer ADENOSINE, and the P2 receptors, which prefer ATP or ADP.	Methyladenine Receptors,Purine Receptors,Purinergic Receptor,Purinergic Receptors,Purinoceptors,Purine Receptor,Purinoceptor,Receptors, Methyladenine,Receptors, Purine,Receptor, Purine,Receptor, Purinergic
D002413	Cations, Divalent	Positively charged atoms, radicals or groups of atoms with a valence of plus 2, which travel to the cathode or negative pole during electrolysis.	Divalent Cations
D005260	Female		Females
D000067956	Adenylyl Cyclase Inhibitors	Compounds that bind to and inhibit the action of ADENYLYL CYCLASES.	Adenylate Cyclase Inhibitors,Cyclase Inhibitors, Adenylate,Cyclase Inhibitors, Adenylyl,Inhibitors, Adenylate Cyclase,Inhibitors, Adenylyl Cyclase
D000241	Adenosine	A nucleoside that is composed of ADENINE and D-RIBOSE. Adenosine or adenosine derivatives play many important biological roles in addition to being components of DNA and RNA. Adenosine itself is a neurotransmitter.	Adenocard,Adenoscan
D000262	Adenylyl Cyclases	Enzymes of the lyase class that catalyze the formation of CYCLIC AMP and pyrophosphate from ATP.	Adenyl Cyclase,Adenylate Cyclase,3',5'-cyclic AMP Synthetase,Adenylyl Cyclase,3',5' cyclic AMP Synthetase,AMP Synthetase, 3',5'-cyclic,Cyclase, Adenyl,Cyclase, Adenylate,Cyclase, Adenylyl,Cyclases, Adenylyl,Synthetase, 3',5'-cyclic AMP
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014970	Xanthines	Purine bases found in body tissues and fluids and in some plants.